Can't tell when visible or not (cube problem)

[510586]

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Hey everyone, in this question on bootcamp, is the there a second cube in the very front (looking from right side)? I thought there was no cube there since we can't assume a cube to be there unless we see an outline or another cube is on top of it.

 

[510586]

I can't tell if there is a cube behind the cube in the very front (when looking from the front) as well.

 

[FloorMatt]

Wow, both are terrible questions. if that was ever on the DAT I think their would be a ton of lawsuites and people complaining. I havent taken the DAT yet but I think its safe to say they wont make illusions that you can't figure out

 

[510586]

Wow, both are terrible questions. if that was ever on the DAT I think their would be a ton of lawsuites and people complaining. I havent taken the DAT yet I think its safe to say they wont make illusions that you can't figure out

The way that BC teaches you to approach these is that you cannot assume a cube is there unless you see its outline or another cube is on top of it. I believe on the second question shown, they count 19 cubes even though I only see 18 (assuming the 2nd cube is hidden). Really hope someone can clear these up, as this is a pretty important concept to understand.

 

[daniho]

I'm pretty positive both figures have blocks in the "hole" that you're referring to.
I understand where you're coming from, but at the same time, I don't think that a column of blocks can just be free "floating" like that and only attached at the corner. That's why they're counting 19 blocks in the second figure. You have a row of 3 blocks on the very left hand side - not 2.

 

[510586]

I'm pretty positive both figures have blocks in the "hole" that you're referring to.
I understand where you're coming from, but at the same time, I don't think that a column of blocks can just be free "floating" like that and only attached at the corner. That's why they're counting 19 blocks. Because in the second figure, you have a row of 3 blocks on the very left hand side. Not 2.

But there is not a free floating block

 

[510586]

I'm pretty positive both figures have blocks in the "hole" that you're referring to.
I understand where you're coming from, but at the same time, I don't think that a column of blocks can just be free "floating" like that and only attached at the corner. That's why they're counting 19 blocks in the second figure. You have a row of 3 blocks on the very left hand side - not 2.

Oh shoot do you mean that there cannot be a column touching by corner alone? That they must have a cube adjacent?

 

[daniho]

I mean it's technically not "free floating", but in each of the figures, each column beside the "hole" is only attached at a corner.

 

[daniho]

Exactly

 

[510586]

Exactly

Alright awesome. I think I'm gonna wait for Ari or someone to come confirm this. If this is true then I can probably improve my PAT score by 1 or 2 points instantly

 

[Mushibachan]

I'm pretty positive both figures have blocks in the "hole" that you're referring to.
I understand where you're coming from, but at the same time, I don't think that a column of blocks can just be free "floating" like that and only attached at the corner. That's why they're counting 19 blocks in the second figure. You have a row of 3 blocks on the very left hand side - not 2.

She's right. The squares can only be connected through their FACES. They will NEVER be attached only by the corners.

 

[510586]

She's right. The squares can only be connected through their FACES. They will NEVER be attached only by the corners.

Sweet. thank you everyone!

 

[neoking77]

What about this lovely thing? How many cubes do you guys count here? I count 21 by not assuming that there are No cubes down the arrows. Is this correct? A lot of fricking corner attachments here.

Source: http://forums.studentdoctor.net/threads/cube-counting.730281/

Edit: After reading the source thread, it appears that the 'must be connected by a face' is an urban myth that spread through SDN. There is no rule that says that. I guess you just have to obey the 'assume there's no cube there unless it indicates otherwise' and roll with that.

Edit 2: cacajuate has cleared it up. In this figure you don't "see" any portions of the cube at all so you assume they're not there. In the first 2 figures of this thread, you "see" portions of the cubes where there *could* be cubes so you assume continuity. Following this principle should get you the right # of cubes.

 

[510586]

What about this lovely thing? How many cubes do you guys count here? I count 21 by not assuming that there are No cubes down the arrows. Is this correct? A lot of fricking corner attachments here.

Source: http://forums.studentdoctor.net/threads/cube-counting.730281/

Edit: After reading the source thread, it appears that the 'must be connected by a face' is an urban myth that spread through SDN. There is no rule that says that. I guess you just have to obey the 'assume there's no cube there unless it indicates otherwise' and roll with that.

Can someone please confirm this? AUGH

 

[Mushibachan]

What about this lovely thing? How many cubes do you guys count here? I count 21 by not assuming that there are No cubes down the arrows. Is this correct? A lot of fricking corner attachments here.

Source: http://forums.studentdoctor.net/threads/cube-counting.730281/

Edit: After reading the source thread, it appears that the 'must be connected by a face' is an urban myth that spread through SDN. There is no rule that says that. I guess you just have to obey the 'assume there's no cube there unless it indicates otherwise' and roll with that.

where did you get that ancient looking picture? LOL

 

[cacajuate]

What about this lovely thing? How many cubes do you guys count here? I count 21 by not assuming that there are No cubes down the arrows. Is this correct? A lot of fricking corner attachments here.

Source: http://forums.studentdoctor.net/threads/cube-counting.730281/

Edit: After reading the source thread, it appears that the 'must be connected by a face' is an urban myth that spread through SDN. There is no rule that says that. I guess you just have to obey the 'assume there's no cube there unless it indicates otherwise' and roll with that.

There are no blocks here.

On the previous two, you assume continuity, so there are blocks on both pictures. You better believe there are going to be a question like that on the DAT.

 

[neoking77]

where did you get that ancient looking picture? LOL

I found it on this thread http://forums.studentdoctor.net/threads/cube-counting.730281/, and the OP of the thread claims it's from Kaplan.

 

[neoking77]

There are no blocks here.

On the previous two, you assume continuity, so there are blocks on both pictures. You better believe there are going to be a question like that on the DAT.

I agree with you. I guess the vague part is when to assume continuity and when you don't

But to rationalize vaguely, for some reason it makes intuitive sense to assume there are cubes in the holes of the first 2, while it doesn't make intuitive sense to assume there'd be 1 or 2 blocks on top of each other in the holes of the 3rd Kaplan pic.

 

[cacajuate]

I guess the vague part is when to assume continuity and when you don't

On the last picture, there is no way for you too "see" if anything is there. Where the previous two had at least some portion of the block shown.

 

[neoking77]

On the last picture, there is no way for you too "see" if anything is there. Where the previous two had at least some portion of the block shown.

I see, thanks for pointing that out. So then I guess when you see a portion of the cube, you assume it's there to allow the cubes to connect better since it just makes more sense from a structural integrity standpoint or sth like that.

With this in mind, do you guys count 18 cubes in the first figure? Is that the correct answer?

 

[cacajuate]

I see, thanks for pointing that out. So then I guess when you see a portion of the cube, you assume it's there to allow the cubes to connect better since it just makes more sense from a structural integrity standpoint or sth like that.

Yes, basically.

 

[DragoBlue]

just did this test. Either PAT 5 or 6. I counted that as a no cube since, like you said, we weren't shown any outline of the cube. Got -1 🙁

 

[cacajuate]

I see, thanks for pointing that out. So then I guess when you see a portion of the cube, you assume it's there to allow the cubes to connect better since it just makes more sense from a structural integrity standpoint or sth like that.

With this in mind, do you guys count 18 cubes in the first figure? Is that the correct answer?

Yes, 18.

 

[neoking77]

just did this test. Either PAT 5 or 6. I counted that as a no cube since, like you said, we weren't shown any outline of the cube. Got -1 🙁

See cacajuate's post to learn why you should count it in the case of the bootcamp pics (first 2) and why you shouldn't in the kaplan pic (3rd pic) in this thread.

 

[DragoBlue]

@neoking77 @cacajuate Holy cow, okay i see. No wonder i always get 13-14/15 every time -.- Thanks for clearing that up guys.

 

[elhammy]

Don't stress yourself out with these type of questions as they weren't an accurate representation of the DAT
Cube counting was more along the lines of Kaplan level (easy).😉