My wicked sick PAT tutorial

[Sama951]

Ok, so, because I have an english midterm tomorrow that I don't want to study for, and because there's 600 posts about how impossible TFE is, and also because I'm good at TFE and feel like being a hero, I'm gonna make a little tutorial where I post a couple of them and talk you through the answer! After I do that, you can scan/post any other ones you want and I'll do my best to explain them. I don't use any weird strategies, I just look at the lines and visualize it in 3D. The tips and tricks you hear about might help narrow it down in some cases but if you can visualize it properly you'll be able to get every question every time.

Oh and excuse the fact that there's writing all over my examples, haha.

Ok first one..

Alright this is a good example for explaining what solid and dashed lines mean.

I assume everyone knows what the different views represent... If not then think of it this way... Imagine a person looking into a camera lens.

A straight up mugshot of the person's face is a "Front" view. Now if you take the camera and move it up, then pivot it and aim it downwards, you've got a "Top" view. Now for the end view, take the camera and put it back in front of the person's face...then you'd take a side-shot of the person's left cheek (but since you're the camera man and you're facing them, you're moving the camera to your right side).

Ok great.

First, looking at the top view, you have one solid line that goes all the way across, from left to right. That means that from a side view, you're only going to have one change in height. Now remember that a straight line like that can mean a straight up drop in height, or it can mean there's a slope with a gradual decline. Looking at all the answers though, it's pretty obvious that we're not looking at any slopes. However, every one of the answers has a single drop in elevation on the top part, so that little bit of information isn't going to narrow it down too dramatically. But... dun dun dun.. look at choice C. Choice C does have a drop in elevation at the top, which is what we decided we're looking for, but it's got the drop at the position of one of the dashed lines (you can tell by the position and thickness of the notch). That's bad! I'm sure this is a trap some people fall into, but yeah, don't. Look at "Fig 1" to see which solid line I'm talking about and where it corresponds to a drop in height in each of the answers (green). Red line = danger = don't fricken do it. Dashed lines do not represent any changes in elevation on the surface they appear on (did that make sense?). Dashed lines are there to show you that there's some kind of height difference deeper into the object, or on the other side all together (what I mean is, it could be a hole that passes through the middle of the object, I'll explain more later if I find an example)

Fig 1

On to the dashed lines we go.

So we've got three horizontal dashed lines on the top view. That means that somewhere in the object, you've got at least 3 extra "walls" (you'll see why I say 'at least' in a second). In other words, there's some kind of height change somewhere that isnt visible from the top. Based on the relative positions of the lines, you'll be able to figure out where the 'height' differences are supposed to be.

Let's compare this to the answer choices. Choice A has 3 walls that you cant see from the top view, D has 4. However, look at the orange line in Fig 2 with the question mark. This wall is lined up perfectly with the blue height change that we discussed above. Because of this, its dashed lines won't show up in the top view (for no reason other than the fact that if you draw a solid line on top of a dashed line...you get a solid line ).

All the walls are spaced apart proportionally to the dashed lines in the top view of the original figure in A and D. Look at B though, it only has 2 of these "walls" that we established you couldn't see from the top. Look at Fig 2. Green = good, red = bad, blue = done, orange = tricky POS.


Fig 2

Great, so we've narrowed it down to A or D. We've done about all we can do with the top view so let's go to the front view. Here we've got 2 solid lines, so from a head-on view, there's 2 height changes. From everything I've said so far about the top view, this should be really easy to figure out, so I'm just gonna include a final figure (green = solid lines and what they correspond with, blue = stuff we already talked about, red = why D is wrong, and orange = dashed lines and what they correspond to)

Notice also how high up the notches go in D, I've highlighted them in red. You should notice that these are way, way higher up than the dashed lines on the front view, so that's another way to eliminate it.

Fig 3

Alright so after all that we can safely conclude that the answer is indeed C.



Just kidding..........It's A.

So yeah, that took way longer than I thought it would and I'm thinking it might have been too simple of an example to be helpful... I hope it helps someone though. If someone can find a really hard one they want me to go through post it here.

Oh crap.. exam tomorrow

---

Members don't see this ad.

 

[2thDMD]

can someone help me with the attached keyhole problem please?

I just can't seem to understand it.


And thanks so much for this thread...its def a life saver

I just opened this and as I quickly look at it, I'm pretty sure the answer is "A" or "B".

Since this is a Crack DAT PAT figure, I'll try and verbally walk you through my thought process (instead of marking up the drawing, which would require written permission from Crack DAT PAT).

Give me a second to think how best to explain the negations, thus leaving you with the correct answer...

2thDMD (Justin)

 

[2thDMD]

can someone help me with the attached keyhole problem please?

I just can't seem to understand it.


And thanks so much for this thread...its def a life saver

Okay futuredentista, here's an explanation to your post.

It's rather lengthy because it's verbal as opposed to my pictorial explanations of past, but hopefully it makes sense.

2thDMD (Justin)



Okay, let me give you some words to refer to some things on the given figure so that we’re all talking about the same appendages, as it were.
In the given figure, let’s call the post sticking up towards 12 o’clock (or on the top of the cube as we see it now in the given figure), the “Big Post”, and the one that is pointing towards 5 o’clock, the “Small Post”. Then on the 7 o’clock / 2 o’clock axis you have what appears to be a “hole” running through the figure.

The way I first looked at this was, “Okay, I have a hole….if any of the possible answer choices show a hole, is it in the correct position relative to everything else on the figure I was given?” So, I look at answer “C” first, since it’s the only answer with a hole in it. Here’s a quick way to negate answer “C”. Look at the given figure. If you were looking at the given figure so that you could see all the way through the hole, no matter which end of the hole you are viewing, you’ll notice that you are also looking at the widest part of the “Big Post”. So, if you can see down the hole from your vantage point, you MUST also be looking at the widest possible side of the “Big Post”. Answer “C” doesn’t show this. Answer “C” shows a possibly correct answer (hole on the left, “Big Post” on the right), but the “Big Post” is not wide in Answer “C”, it is narrow. Also, If you were to rotate the given figure to look like Answer “C”, you’d need to have the “Small Post” pointing out toward 9 o’clock from the side of Answer “C” (coming off the left side of Answer “C” where the hole is). Since the “Big Post” is not wide enough, and you’re missing the “Small Post” altogether from Answer “C”, Answer “C” is not correct.

Since Answer “D” is similar in size and shape, that’s the next one I go to. Ask yourself, “Is there any way to position the given figure so that I can see the widest (or flattest) side(s) of the “Big Post”, AND have the “Big Post” on the LEFT-hand side as it points upwards above the cube?” Remember, in the given figure, the “Big Post” is on the top of the cube, so if you were to just let the given figure fall away from you (back behind the plane of the screen/page) and land flat on it’s bottom, then no matter how you spun the figure (horizontally…like a hula hoop), the “Big Post” would always be facing upwards towards 12 o’clock. Okay, now back to my question, “Is there any way to position the given figure so that I can see the widest side(s) of the “Big Post”, AND have the “Big Post” on the LEFT-hand side as it points upwards towards 12 o’clock?” The answer is yes. You could rotate the given figure in such a way that Answer “D” would look correct, however, you wouldn’t be seeing the widest part of the “Big Post”, you’d be seeing the narrowest part. Best way to describe what I’m envisioning is this way….Imagine the given figure is sitting in the very center of a clock dial. If you were at 10 o’clock and looking towards 4 o’clock, it would look somewhat like Answer “D”, but remember, Answer “D” is showing you the widest part of the “Big Post”, whereas if you envision the positioning I just told you to do (looking from 10 o’clock towards 4 o’clock), you’d actually be seeing the narrowest part of the “Big Post”. The tricky part for some people is that the widest / narrowest part of Answer “D” is the only thing that negates it. In looking at Answer “D”, the hole would be running from 9 o’clock to 3 o’clock behind that base block (and therefore wouldn’t be seen….which coincides with the given figure), and the “Small Post” would be sticking out the back of Answer “D”, so you’re not technically missing that element, you just can’t see it in Answer “D”, but it is still there. The width of the “Big Post” in Answer “D” is the only giveaway that it is wrong.

Okay, it’s NOT Answer “A” as I had originally speculated as possible. Everything checks out to make it look like Answer “A” is correct, except the placement of the “Small Post”. The “Small Post” on the left side is doable, and it is in the right size/proportion. However, it is in the wrong Position….not high enough up on Answer “A”. Try visually rotating the given figure so that 1) the hole is on the top of the figure, 2) the “Big Post” is coming out at you (therefore you can’t see it), and 3) the “Small Post” is on the LEFT-hand side of the figure…just as shown in Answer “A”. Now, refer back to the given figure. Notice how the “Small Post” is a lot closer to the top where the hole is? It’s more than ½ way up the side of that wall that it is attached to. But, in Answer “A”, it’s much closer to the bottom of the figure and below the centerline of that wall that it is attached to. So, Answer “A” is wrong.

So, that leaves us with Answers “B” and “E”.
Let’s try and match up the “Big Post” on both the given figure and Answer “E” to see if the other posts / things line up. In order to make the “Big Post” in the given figure wind up on the RIGHT-hand side pointing toward 3 o’clock, the “Small Post” would have to be pointing down…which it is. Here comes the sticking point; If you were to rotate the given figure to match Answer “E”, you’d also be looking down the hole (front to back, in Answer “E”), which you are obviously not. So, Answer “E” is incorrect.

Answer “B” is the right choice.
Just to kind of walk you through why Answer “B” is the right choice…imagine yourself grabbing the “Big Post” in the given figure and bringing it towards yourself so that it disappears into the main form when you are looking at it head-on. Now, rotate the given figure clockwise a little bit so that the “Small Post” is pointing down. The hole would be behind the center mass (running from 9 o’clock to 3 o’clock…like in Answer “B”).

2thDMD (Justin)

 

[futuredentista]

Thanks soo much! that totally helped!

 

[prsndwg]

Can someone help me out with these two please:

Thanks

 

[alanan84]

I don't feel like counting cubes but the keyhole looks like D to me

 

[navneetdh]

Can someone help me out with these two please:

Thanks

Is it:

8 cubes with 3 sides

and C for the hole punching?

 

[prsndwg]

Is it:

8 cubes with 3 sides

and C for the hole punching?

Now i figured out the key holes... can you tell me how u counted 8 cubes? i keep getting 7!

 

[BoxerRumble]

Now i figured out the key holes... can you tell me how u counted 8 cubes? i keep getting 7!

What's the answer to the 2nd question? Is it C?

 

[prsndwg]

What's the answer to the 2nd question? Is it C?

yup

 

[navneetdh]

Now i figured out the key holes... can you tell me how u counted 8 cubes? i keep getting 7!

Sorry it is late but I am not too sure about how to mark on the picture itself. So bear with me for this crummy explanation for the cubes.

Ok start with the left most side of the picture.

you see 2 columns (heights or pillars) each contain 2 cubes
each of these pillars has 1 cube with 3 faces painted(one top cube and the pillar behind has bottom cube). so = 2

then you see 2 more and these have 2 cubes each too. Each pillar again has 1 cube with 3 faces. So 2 more =4 so far

now keep moving along to the right...another pillar with 2 cubes. The base cube of this is 3 faced. SO 5 so far.


now you come to the tallest pillar which has 5 cubes. The 4th cube from top is 3 faced. So 6 so far.


behind it is just 1 cube sitting on the floor. This is also 3 faced. So 7 so far.
and behind that is a pillar with 2 cubes. The base cube of this is 3 faced. So 8

I hope that explains. I am extremely sorry for not being able to show it with a picture.

 

[BoxerRumble]

Sorry for the small pic, just click on it and it'll give you a bigger one. Just wanted to give back to this thread since it's been so helpful. I think you were missing either the one below the box w/ the arrow or the one on the bottom surround by other cubes. Hope this helps!

 

[Pwn]

Thank you guys so much for this thread, it's helping a ton!

 

[prsndwg]

Sorry for the small pic, just click on it and it'll give you a bigger one. Just wanted to give back to this thread since it's been so helpful. I think you were missing either the one below the box w/ the arrow or the one on the bottom surround by other cubes. Hope this helps!

perfect thnak you

 

[navneetdh]

So i have read many posts and they say DAT PAT is about at par with CDP sometimes more tuff. People usually get a score in the range they get in CDP.

I took a few CDP test over the past 2-3 weeks and here are my scores.

test# score

1 16
2 18
3 18
4 19
5 20
7 18

I do good on key holes, i get 13 or more avg on TFE, I get 13 or more avg on cubes unless they have an illusion, and I am guessing there are no illusions on DAT. Hole punches i was doing bad but i have improved in last 2 tests a lot.
My worst by far are the angles. I get like 6 or 9 in there. I try the hill, laptop and fit in methods. I just cant seem to tell apart angles that are 4 degrees or less apart.
I dont do well with pattern folding either.

I am really stressed about these two sections. It brings my score down a lot. I really have to beat a 20 atleast on the PAT.

Please give me advice? How can I improve? what should I do about the stupid angles and pattern folds?? If I stay in the low range in CDP that means i wont even be able to do well in DAT.

how can i improve????

 

[2thDMD]

Can someone help me out with these two please:

Thanks

Yes, the answer is C.

Think of it this way. Look at the given figure. The long, flat side that is closest to you (the one that is perpedicular to the (unseen) table it is resting on, not the side that is multidimensional and parallel to the table)...think of that as the base. Now, this "base" has two ends...the one that is closer to you has a diagonal slant (pointing down towards 6 o'clock), and the one that is at the other end is square (but is obscured from view because of the base itself).

So, stand this figure up on it's "base".
Now rotate the figure so that the square (which you can't see) at the far end of the base is pointing directly at you, and the other end of the base (the downward diagonally sloping end), is furthest away from you and pointing away from you.

It can only look like answer "C".

Hope this helps.

2thDMD (Justin)

 

[mashimlro]

I like this thread!

 

[2PacClone23]

Yes, the answer is C.

Think of it this way. Look at the given figure. The long, flat side that is closest to you (the one that is perpedicular to the (unseen) table it is resting on, not the side that is multidimensional and parallel to the table)...think of that as the base. Now, this "base" has two ends...the one that is closer to you has a diagonal slant (pointing down towards 6 o'clock), and the one that is at the other end is square (but is obscured from view because of the base itself).

So, stand this figure up on it's "base".
Now rotate the figure so that the square at the one end of the base is directly pointing at you, and the other end of the base (the downward diagonally sloping end), is furthest away from you and pointing away from you.

It can only look like answer "C".

Hope this helps.

2thDMD (Justin)

Can't be C. D looks just about right. Anyway you turn the figure, the shape of C would not fit.

 

[dufran3]

It cannot be D, the block piece isn't shaped like that, it needs to have another "step" in it going up.

 

[S2000]

It looks like this one could possibly be A but the correct answer is C. Any ideas? By the way, this is a great thread. Thanks everyone, esp. Sama, for the help. I just scored a 14 on my analysis PAT on DAT achiever . Should I get Crack DAT PAT for the PAT stuff instead?

 

[Shingo123]

It looks like this one could possibly be A but the correct answer is C. Any ideas? By the way, this is a great thread. Thanks everyone, esp. Sama, for the help. I just scored a 14 on my analysis PAT on DAT achiever . Should I get Crack DAT PAT for the PAT stuff instead?

2 possibilities:

1: The size of the shape in A is too small.
2: Notice that little line on the tip of the x structure on the shape? That is not accounted for in a, BUT is in C, where you can see the the inner bumb is higher.

 

[S2000]

2 possibilities:

1: The size of the shape in A is too small.
2: Notice that little line on the tip of the x structure on the shape? That is not accounted for in a, BUT is in C, where you can see the the inner bumb is higher.

Thanks. I wasn't sure if the picture was supposed to be assumed to be the same size. Makes sense, I noticed the triangle on the tip of the x and thought the tip was in line with the hexagon.

 

[Shingo123]

Thanks. I wasn't sure if the picture was supposed to be assumed to be the same size. Makes sense, I noticed the triangle on the tip of the x and thought the tip was in line with the hexagon.

Yeah, the size of an object is usually not a distinguishing factor, however it does show up, so watch out for it.

 

[solstice]

I love your tutorial, but I have problem with more complex pictures. This image forexample, as soon as I see it, I just wanta choose something and move forward in hope for better ones, and therefore I have not been able to get good scores in TFE. Please help explain this if you can.

Sorry I am knew to the forum and don't know how to put a picture here.

 

[2thDMD]

Yes, the answer is C.

Think of it this way. Look at the given figure. The long, flat side that is closest to you (the one that is perpedicular to the (unseen) table it is resting on, not the side that is multidimensional and parallel to the table)...think of that as the base. Now, this "base" has two ends...the one that is closer to you has a diagonal slant (pointing down towards 6 o'clock), and the one that is at the other end is square (but is obscured from view because of the base itself).

So, stand this figure up on it's "base".
Now rotate the figure so that the square at the one end of the base is directly pointing at you, and the other end of the base (the downward diagonally sloping end), is furthest away from you and pointing away from you.

It can only look like answer "C".

Hope this helps.

2thDMD (Justin)

Can't be C. D looks just about right. Anyway you turn the figure, the shape of C would not fit.

Ahhhhh, young Grasshopper....the pebble in my hand still eludes you.
Just kidding.
I created a 3-D model to show you why it is, in fact, "C".

2thDMD (Justin)


UPDATE: 7/24/2014....It would appear that these 3D images have been deleted from the host server. I will see if I can locate them and repost them.

UPDATE: 7/25/2014....I can't find the pictures on the server, and having just moved to a new city, my 3D rendering software is packed away. So, I don't have access to the software to recreate the Swift 3D Animation that was embedded in this post before. If I unpack it soon, I will redo it and repost it.

In the meantime, I've come up with a static explanation that should suffice.

See the aqua green panel?
Stand the object up on the table so that the aqua panel is the base panel of the object.
Now, with your right hand, pivot the object toward you until the red dot is in the upper left corner and the blue dot is on the lower left corner of the object (resting on the table top).
Answer "C".

 

[2thDMD]

I love your tutorial, but I have problem with more complex pictures. This image forexample, as soon as I see it, I just wanta choose something and move forward in hope for better ones, and therefore I have not been able to get good scores in TFE. Please help explain this if you can.

Sorry I am knew to the forum and don't know how to put a picture here.

Hey Solstice,

Yeah, this type of TFE is specifically intended to be a time vortex. They want you to spend alot of time trying to figure out this type of problem, thus leaving you with much less time to figure out the others. WRT to brain-benders like this one, best thing to do is to Mark it and come back to it. Get some definite right answers under your belt (so that you have a good PAT score base), then come back (if you have any time left) and try to get these for an extra little bump in your score.

It took me a little longer than usual to get this one, but it is in fact "B". Once I looked at 2 key pieces (separately and in relation to each other), it became pretty obvious. I would turn it into a tutorial and post it, but I think the artwork belongs to Crack DAT PAT and I'd have to get written permission in order to do that.
If you really, really must know how this one is solved, I'll try to think of a way to verbally walk you through it (that doesn't take the better part of a phonebook to explain).

2thDMD (Justin)

 

[2PacClone23]

I just got pwned.

 

[S2000]

Sorry to keep posting questions, but I'm scoring very dismal in the PAT only 15 on Achiever

Correct answer: C

Correct answer: D

 

[dufran3]

ummm...I replied to the original image...but you changed it....argg

 

[S2000]

ummm...I replied to the original image...but you changed it....argg

I apologize! haha, I found some harder ones

 

[drpoppapump]

 

[2thDMD]

The answer should be "A", because the way this is drawn, you can't be sure that the backside of this figure is in fact concaved (as they want you to think it is). It is most likely straight-backed, so if you rotated it to the right (on a horizontal plane), you'd wind up with figure "A".

Answer B is wrong for the same reason...you can't be sure what the backside looks like.

Answers C and D are wrong for obvious reasons (which I can explain if somebody really wants me to).

Answer E looks very inviting and if you aren't paying attention and in a hurry, you'll pick that one and move on. But it's wrong for so many reasons.

Let's look at the 3 triangles we can actually see (the ones that give depth to the figure).

There is a triangle on the top, a triangle on the bottom and a triangle pointing right.

Let's look at the top triangle first. Look at the three lines coming down from that top point. From left to right, let's label these lines 1,2 & 3, respectively. That third line (the one that faces down just to the RIGHT of 6 o'clock) is missing.

Now look at the bottom triangle....let's call the lines from left to right 1,2 and 3 respectively. In Answer E, line # 3 on the bottom triangle is not there.

Now let's look at the triangle on the right. Let's look at the three lines involved, and from top to bottom let's label them 1,2 and 3, respectively. For the triangle on the right, line # 3 is not there in Answer E.

If you think about it a little deeper (no pun intended) line # 3 in all of the triangles that we can see give the given figure depth. However, if you were to leave the given figure the same shape and take the depth out of it...it would then look very close to Answer E....but still not be correct.


2thDMD (Justin)

 

[navneetdh]

answer is C. Why cant it be A?



answer is C. Why cant it be B



Answer is C. WHy cant it be B



answer is B. WHy cant it be C



answer is D. why cant it be C?


I am really sorry about the links. I just dont know how to get the picture posted on the post. It just wouldnt show the picture. Thank You

 

[UCB05]

answer is C. Why cant it be A?



answer is C. Why cant it be B



Answer is C. WHy cant it be B



answer is B. WHy cant it be C



answer is D. why cant it be C?


I am really sorry about the links. I just dont know how to get the picture posted on the post. It just wouldnt show the picture. Thank You

1. In the top view, you can see that the upper half of the point side is solid. For A to be true there would need to be another solid horizontal line on that edge



2. For B to be true, the two vertical dashed lines would have to be solid, since they project above the base.



3. To compensate for the slanted lip on B, there would have to be a solid vertical line through the base in the front view and a dashed mid-way vertical line through the end view.



4. The top elevation in choice C seems two narrow in width to be the answer.

5. The tapered end in choice C seems too long

 

[navneetdh]

1. In the top view, you can see that the upper half of the point side is solid. For A to be true there would need to be another solid horizontal line on that edge



2. For B to be true, the two vertical dashed lines would have to be solid, since they project above the base.



3. To compensate for the slanted lip on B, there would have to be a solid vertical line through the base in the front view and a dashed mid-way vertical line through the end view.



4. The top elevation in choice C seems two narrow in width to be the answer.

5. The tapered end in choice C seems too long

Thank YOu Sooooo much. That helped a lot...especially for the TFE.

When You were trying to figure this out did you feel the differences between the 2 choices were very minute? I thought they were and could barely notice them---obviously. I am asking you because it would help me know if I am seriously missing something here and need a lot of work or it really was realistically a close call.

But still Thank You so much

 

[drpoppapump]

awesome help guys.. how about this one

 

[2thDMD]

awesome help guys.. how about this one

Okay, with the answer choices given in this one, we should be able to quickly negate down to the two best answer choices.
If you laid the given figure on it's left side (i.e.: came up to it from the right side as it is shown right now, and kicked it over), you'd have something (and I use this term very loosely) similar to Answers "C" and "D".

Answer C is wrong because you'll notice in the given figure, the peg at the top of the figure is taller than the peak, so laying down on it's left side, you'd have a vertical line that extended past the peak. This is absent in Answer "C". Also, if you look a the given figure, the square block that the peg is mounted into has a diagonal downward facing angle on it's bottom side, but it terminates into the body of the main part of the figure. In Answer "C", that downward diagonal line goes all the way to the base of the figure, which is not correct.

Answer "D" is incorrect because of the same "peg" reasoning, but also because the square block that the peg is mounted to is nowhere near that deep (and therefore nowhere near that tall when the figure is laid on it's side).

Answer "E" is wrong for a number of obvious reasons.
Once again, the peg in the given figure is higher than the apex of that top wedge, so Answer "E" should have some horizontal line toping that figure (above the peak), which it doesn't. Also, the block coming out of the back of the figure (the one that the peg is attached to)...notice that the surface of that block that the peg is attached to is flat and that there are no beveled corners on the side the peg attaches to the block. But in Answer "E", even if we could get by the fact that there isn't a peg silhouette, that block (in Answer "E") has a beveled edge on top, which it doesn't in the given figure. Furthermore, the block in the given figure (as mentioned previously), terminates in the body of the main figure with a diagonally downward line. In Answer "E", the block goes all the way to the base.

So, that leaves us with Answers "A" and "B".

Answer "B" you should be able to negate pretty quickly due to the fact that the block on the back of the given figure has that bottom downward diagonal, which Answer "B" doesn't have. Also, if you look at the example they give you, the inward taper near the top starts in the middle of the block with the peg in it...but in answer "B", the taper finishes before you even encounter the block.

So, the answer must be "A" (flip the figure 180*, CCW, IN the plane of the paper).

The only thing I don't like about some of these problems is that whichever company produced these illustrations, they're relational aspects are sometimes a little off, which can cause those who are not strong in this subject, a little more headache.
What I mean by "relational aspects" is this....look at the given figure....look at the peg...it's the highest point in the object and is flat-topped....then the next point of interest down is the square that the peg is resting on top of (and it too is flat-topped)....then the next point of interest down is where the sides of the wedge start to lean in towards the apex.

So, from top to bottom we have:

1. The flat-topped peg
2. The flat-topped square, and (then a least a couple pixels down)
3. The point where the vertical lines start tapering inward to form the wedge.

...in this order, top to bottom.

Now, take the given figure and rotate it CCW, 180* in the plane of the paper so that it looks like Answer "A".
If we look at the figure from the bottom up, we should have the same chronology as the top down, namely:

1. The flat-topped peg
2. The flat-topped square, and (then a least a couple pixels up)
3. The point where the vertical lines start tapering inward to form the wedge.

...but, we don't.
If you look closely at Answer "A" (which is still correct, btw, I'm just speaking about "relational aspects" that make it harder for some students to grasp TFE's),...if you look at Answer "A" and go from the bottom up, you have:

1. The flat-topped peg
2. then...The point where the vertical lines start tapering inward to form the wedge, and
3. then...The flat-topped square.

Most people don't notice these things, but they are the kind of details that drive me crazy, and the kind of subtle differences that I'm sure play tricks on people who don't like TFE's to begin with.

Lastly, since the peg is higher (horizontally) than the apex of the wedge (in the given figure), Answer "A" should be propped up on a peg silhouette, then have (a couple of pixels higher), the diagonally sloping line. But, in Answer "A" the diagonal line coincides with the top of the peg, which is "technically" incorrect,...but for the purposes of this Q&A / explanation, it is what the question-makers settled for as a correct answer.

2thDMD (Justin)

 

[drpoppapump]

Okay, this one should be quick negate down to your two best answer choices.
If you laid the given figure on it's left side (i.e.: came up to it from the right side as it is shown right now, and kicked it over), you'd have something (and I use this term very loosely) similar to Answers "C" and "D".

Answer C is wrong because you'll notice in the given figure, the peg at the top of the figure is taller than the peak, so laying down on it's left side, you'd have a vertical line that extended past the peak. This is absent in Answer "C". Also, if you look a the given figure, the square block that the peg is mounted into has a diagonal downward facing angle on it's bottom side, but it terminates into the body of the main part of the figure. In Answer "C", that downward diagonal line goes all the way to the base of the figure, which is not correct.

Answer "D" is incorrect because of the same "peg" reasoning, but also because the square block that the peg is mounted to is nowhere near that deep (and therefore nowhere near that tall when the figure is laid on it's side).

Answer "E" is wrong for a number of obvious reasons.
Once again, the peg in the given figure is higher than the apex of that top wedge, so Answer "E" should have some horizontal line toping that figure (above the peak), which it doesn't. Also, the block coming out of the back of the figure (the one that the peg is attached to)...notice that the surface of that block that the peg is attached to is flat and that there are no beveled corners on the side the peg attaches to the block. But in Answer "E", even if we could get by the fact that there isn't a peg silhouette, that block (in Answer "E") has a beveled edge on top, which it doesn't in the given figure. Furthermore, the block in the given figure (as mentioned previously), terminates in the body of the main figure with a diagonally downward line. In Answer "E", the block goes all the way to the base.

So, that leaves us with Answers "A" and "B".

Answer "B" you should be able to negate pretty quickly due to the fact that the block on the back of the given figure has that bottom downward diagonal, which Answer "B" doesn't have.

So, the answer must be "A" (flip the figure 180*, CCW, IN the plane of the paper).

The only thing I don't like about some of these problems is that whichever company produced these illustrations, they're relational aspects are sometimes a little off, which can cause those who are not strong in this subject, a little more headache.
What I mean by "relational aspects" is this....look at the given figure....look at the peg...it's the highest point in the object and is flat-topped....then the next point of interest down is the square that the peg is resting on top of (and it too is flat-topped)....then the next point of interest down is where the sides of the wedge start to lean in towards the apex.

So, from top to bottom we have:

1. The flat-topped peg
2. The flat-topped square, and (then a least a couple pixels down)
3. The point where the vertical lines start tapering inward to form the wedge.

...in this order, top to bottom.

Now, take the given figure and rotate it CCW, 180* in the plane of the paper so that it looks like Answer "A".
If we look at the figure from the bottom up, we should have the same chronology as the top down, namely:

1. The flat-topped peg
2. The flat-topped square, and (then a least a couple pixels up)
3. The point where the vertical lines start tapering inward to form the wedge.

...but, we don't.
If you look closely at Answer "A" (which is still correct, btw, I'm just speaking about "relational aspects" that make it harder for some students to grasp TFE's),...if you look at Answer "A" and go from the bottom up, you have:

1. The flat-topped peg
2. then...The point where the vertical lines start tapering inward to form the wedge, and then
3. then...The flat-topped square.

Most people don't notice these things, but they are the kind of details that drive me crazy, and the kind of subtle differences that I'm sure play tricks on people who don't like TFE's to begin with.

Lastly, since the peg is higher (horizontally) than the apex of the wedge (in the given figure), Answer "A" should be propped up on a peg silhouette, then have (a couple of pixels higher), the diagonally sloping line. But, in Answer "A" the diagonal line coincides with the top of the peg, which is "technically" incorrect,...but for the purposes of this Q&A / explanation, it is what the question-makers settled for as a correct answer.

2thDMD (Justin)

thanks justin for the thorough answer..the choice is really hard to figure out since it looks pretty flush to the block so i didn't really pay much attention to the bulge and none of the answers came out to me immediately and i assumed it was a or b without a real valid reasoning.

 

[drpoppapump]

blah

 

[Meas]

I have a followup question about the following:

In Doc2 attached, what happens to round edge as indicated by the two black arrows. Does each arrow appear as a vertical line in the top view?

Can someone explain Doc3? I was choosing between B or D.

Thanks!

View attachment Doc2.zip

View attachment Doc3.zip

 

[2thDMD]

I have a followup question about the following:

In Doc2 attached, what happens to round edge as indicated by the two black arrows. Does each arrow appear as a vertical line in the top view?

Can someone explain Doc3? I was choosing between B or D.

Thanks!

Okay, when looking at Answer "C", you'll notice that the sides of the circle coming down past the 9 o'clock and 3 o'clock positions come back in towards the 6 o'clock position before they touch the base that the circle is sitting on. The widest part of the circle would correspond to the solid lines in the Top view and the dashed lines would correspond to the "legs" of the circle that came in under the body of the circle and touch the base the circle is sitting on. Having said this, and keeping the Top View in mind, Choices "A" and "C" are both viable....However...when you take into account the End View, you'll notice that there is that hollow hallway that is behind the main figure when viewed from the front, and under the top of the figure when viewed from the top.

Now, walk into the page and stand where the "?" is. Turn to your right so that you are looking at the Front of the End view. That hollow hallway would be obscured from your view from this position, correct? Therefore, it would be represented as a dashed line....but in Answer "A" the bottom line of the hallway is represented (at least partially) as a solid line. Therefore "A" is out and Answer "C" is correct.

 

[2thDMD]

I have a followup question about the following:

In Doc2 attached, what happens to round edge as indicated by the two black arrows. Does each arrow appear as a vertical line in the top view?

Can someone explain Doc3? I was choosing between B or D.

Thanks!

This one has some "very close" options which make you want to just jump on one and move on, but the answer is "D".

It can't be "A" because the given figure can't be isometrical no matter how you slice it, so it's answer can't be either.

You might want to jump to "B" because it looks very similar if you just stood the given figure on it's point and rotated it (in the horizontal plane) just a little bit. But, in Answer "B", the slope is more severe, and it leads to a notch-up before making a 90* angle with flat side. Answer "B" just has the slope going straight up to the flat side....so "B" is out.

Answer "C" looks really close because it does have the (approximate) correct sloping, the notch-up and the flat side. However, you have to remember your proportions. I think the sticking point here is the base block that the slope is attached to....I think that base block (in "C") is not as wide as it should be to represent the given figure (i.e.: from the back of the base block in the given figure, to where it attaches to the sloping piece...I don't think that this is wide enough).

Now you may be tempted to stand the given figure up so that it looks like Answer "E", at which point the slope would become irrelevant because it would be encompassed by (and fade into) the space between the top and bottom lines of the leg (or base piece) you see in the "L" shape in Answer "E". However, once again, proportion comes into play. When looking at the given figure, and at the ramp/slope specifically, the depth of that ramp/slope looks significantly deeper than the height of the base of the "L" in Answer "E". Also, the cantilevered block in the given figure looks wider than the width of the vertical portion of the "L" in Answer "E".

Now for Answer "D". The best (read: shortest) way for me to describe to you how to rotate this is to use a gun analogy. Think of the given figure as a gun....the ramp/slope is the barrel, and the cantilevered block is the handle. Pick up the gun and point it directly away from you. It looks like figure "D", doesn't it?


2thDMD (Justin)

 

[Chrono]

What is the correct answer that's given for 3?

 

[Chrono]

2 possibilities:

1: The size of the shape in A is too small.
2: Notice that little line on the tip of the x structure on the shape? That is not accounted for in a, BUT is in C, where you can see the the inner bumb is higher.

Could someone please mark the line you guys are talking about?

 

[2thDMD]

I have a followup question about the following:

In Doc2 attached, what happens to round edge as indicated by the two black arrows. Does each arrow appear as a vertical line in the top view?

Can someone explain Doc3? I was choosing between B or D.

Thanks!

View attachment 13435

View attachment 13436

BTW Meas (et. al.), just so everybody on SDN can see the pictures that a post is referring to and doesn't have to download docs or attachments or navigate away from the post itself, I'd recommend hosting your pictures on a site like Photobucket. It's free, and I'll give you a quick little tutorial on how simple it is to add pictures to your post on SDN.


How to include pictures in your SDN posts

1. Acquire the picture you have a question about (maybe you need to scan it or maybe you screenshot it....whatever...find it on your computer).
2. Open up another tab or window and go to www.photobucket.com and get a free account.
3. Upload your pictures.
4. Once your pictures have been uploaded, mouse over the picture you want to include in your post....once you do, a pop-down window like this...
   
   
   
   
   
   ...should appear.
5. Single click your mouse inside the box that says "Direct Link" and it should turn blue.
6. Hit Cmd+C (if on a Mac), or Ctrl+C (if on a PC) to copy the link.
7. Go back to the SDN BB tab (or window) and look for the "Insert Picture" icon, which looks like a little postcard, like this...
   
   
   
   
   
   ...at the top of the window. Click on it.
8. When the new window comes up, hit Cmd+V (if on a Mac), or Ctrl+V (if on a PC) to paste the link to the picture within the HTML parameters.
9. That's it.

I've included your photos to show you how easy it is to "host-n-post" your pictures:

Now everybody can see what you're referring to (picture-wise) because it will all be contained within your post, and it will be easier to follow along with the explanations as well.


2thDMD (Justin)

 

[2thDMD]

What is the correct answer that's given for 3?

This one has some "very close" options which make you want to just jump on one and move on, but the answer is "D".

It can't be "A" because the given figure can't be isometrical no matter how you slice it, so it's answer can't be either.

You might want to jump to "B" because it looks very similar if you just stood the given figure on it's point and rotated it (in the horizontal plane) just a little bit. But, in Answer "B", the slope is more severe, and it leads to a notch-up before making a 90* angle with flat side. Answer "B" just has the slope going straight up to the flat side....so "B" is out.

Answer "C" looks really close because it does have the (approximate) correct sloping, the notch-up and the flat side. However, you have to remember your proportions. I think the sticking point here is the base block that the slope is attached to....I think that base block (in "C") is not as wide as it should be to represent the given figure (i.e.: from the back of the base block in the given figure, to where it attaches to the sloping piece...I don't think that this is wide enough).

Now you may be tempted to stand the given figure up so that it looks like Answer "E", at which point the slope would become irrelevant because it would be encompassed by (and fade into) the space between the top and bottom lines of the leg (or base piece) you see in the "L" shape in Answer "E". However, once again, proportion comes into play. When looking at the given figure, and at the ramp/slope specifically, the depth of that ramp/slope looks significantly deeper than the height of the base of the "L" in Answer "E". Also, the cantilevered block in the given figure looks wider than the width of the vertical portion of the "L" in Answer "E".

Now for Answer "D". The best (read: shortest) way for me to describe to you how to rotate this is to use a gun analogy. Think of the given figure as a gun....the ramp/slope is the barrel, and the cantilevered block is the handle. Pick up the gun and point it directly away from you. It looks like figure "D", doesn't it?


2thDMD (Justin)

Read the first sentence and the last paragraph of my explanation for the answer.


2thDMD (Justin)

 

[2thDMD]

I have a followup question about the following:

In Doc2 attached, what happens to round edge as indicated by the two black arrows. Does each arrow appear as a vertical line in the top view?

I told you what the answer was and why, but I guess I forgot to answer your original question.

I think I know what you were trying to show (and what you're asking), but I'm going to take the "arrows" out of my verbiage because I think I might be able to explain this better without that term.

If you look at Answer "C"...where the sides of the circle are at their widest...those will appear as solid vertical lines in the Top view. Where the sides of the circle come down and touch the base,...those lines will be dashed vertical lines from the Top view because from that angle the circle itself is obstructing your ability to view that junction directly.

Forget about the "roundness" of that circle in "C". They just throw in that extra dimension to mess with your head and get you to waste time contemplating how the roundness figures into the whole picture. Remember, from the Top view, you have no depth perception (aside from implied depth perception due to the dashed vs. solid line rules). So, even though looking at Answer "C" you see that the circle has depth in the horizontal plane (above it's midline plane...as it goes from 9 o'clock up to 12 o'clock and back down to 3 o'clock), when looking at the Top view of the given figure, all you see is a horizontal line. From the top view of the given figure, you have no way to know if that is in fact a straight (i.e.: flat/horizontal) line, or if from some other viewpoint it has height/depth.

So, when doing this particular problem, don't look at the roundness of the circle an let that throw you off. Look at the width of each of the shapes in all of the answers and also where the lines of those shapes are relative to the other lines in that same shape,....then look at the given figure and compare/contrast.

Just to drive the point home....look at Answer "C". Cut that circle in half, horizontally (so that you have the top portion which is from 9 o'clock up to 12 o'clock and back down to 3 o'clock). That is the widest part of that circle, right? Now look at the Top view. That second horizontal line form the bottom of the Top view is the exact same width line of that circle...just from the Top view.

The short-short of this particular problem....if you look at the widest part of the circle, it will tell you how wide the horizontal line (corresponding to the face of the circle is) in the Top view. It will also tell you that (based on the width of the circle), that from the Top view, the vertical lines that are second in from the sides will be solid (because these are the 9 o'clock and 3 o'clock sides of the circle, and hence the widest part of the circle), and therefore the "legs" of the circle (that come in under the circle and touch the base that the circle is resting on), will be the 3rd vertical (dashed) lines from the sides in the Top view.



Hope this helps.


2thDMD (Justin)

 

[navneetdh]

Why is this A and not B?

Why is this C and not B?

for some reason I had a hard time telling the difference between the two answer choices. It was not obvious at all to me and given the little time on the actual test can someone please explain me how to go about these quickly and correctly

 

[navneetdh]

I have no clue how to tell from the given info why it is B and not A. when i saw achiever solutions i thought for both B and A the front and the side views were same. There were no differences---so unless you have the 3d image you couldnt know. Can anyone else try and let me know what I might not be seeing?

Again why will this one be B and not A. Ok I see B can work---why NOT A

why will this one be C and not A?? I dont get the diagonal lines

in the following one answer is E---why not A?? i thought the triangular thing was same height as the square wall. how can you tell it is not?

In the following one the answer is A---I chose B. I dont even know where to fold this thing---i cant tell --the shading is terrible--is it just me?

In the following one the answer is A---I chose C. I didnt get what the hell is that curvy thing and how can it possible be actually seen as the curvy line from the side view.

How can you tell this will be D and not C???

 

[navneetdh]

The answer is A---why not D

the answer is D--why not C??

Thank You for all your help in advance.

 

[NumbaOneStunna]

Wow....