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The scale riddle
1st attempt ----6---6 Choose the ligther load to reweigh it

2nd attempt 3---3 choose the lighter load to reweigh it


3rd attempt 1-----1 if it is equal then chose the leftover. if one is lighter than choose that one
 
The scale riddle

6---6 Choose the ligther load

3---3 choose the lighter load

1- 1 if it is wqual then chose the leftover

Why the lighter load? You don't know if the coin is lighter or heavier, just that it's different.
 
Good grief, why is it every time I have an exam and have to study, this thread blows up with posts and/or awkward tension?

sat-lets-party-webentry.gif

Thanks, friend.

i am cracking up at this thread right now.

i am also wholly convinced that spurs = dictator in gnome riddle.

Sounds about right.
 
I think I've run into trouble on this riddle. I thought I had it, but I realized I wouldn't be able to tell the last 2 apart. Hmmm... Let me think some more.
 
I figured it out!!! For real this time.

EDIT: Do you want me to post my solution?
 
i'm thinking 3 v 3 to start, narrowing it down to 6. but i always have 2 left, without a clue if it's the heavier or the lighter one.

3vs3 at best gives you the abnormal marble without letting you know if its heavy or light


try 4 v 4

1. 2 groups balance = 3rd group has the abnormal one
2. 2 groups dont = break down those 2 groups
 
3vs3 at best gives you the abnormal marble without letting you know if its heavy or light


try 4 v 4

1. 2 groups balance = 3rd group has the abnormal one
2. 2 groups dont = break down those 2 groups

I figured out a way with 3 v 3 that will yield if it is heavy or light. 🙂
 
label your marbles and start with 4 v 4

3vs3 at best gives you the abnormal marble without letting you know if its heavy or light


try 4 v 4

1. 2 groups balance = 3rd group has the abnormal one
2. 2 groups dont = break down those 2 groups

I tried that, but after the first step, it only narrows it down to 8(2 groups), without letting you know if it's heavier or lighter. If you measure one of those groups against the normal group, you CAN get heavier or lighter, but you only narrow it down to 4. And you can't isolate the one abnormal marble from 4 in one step.
 

Here we go:

Scenario 1
3v3 - same, so take 2v2 from other 6
2v2 - same, so you know remaining 1v1 is different
1v1 - take one from the remaining set and weigh it with any of those already weighed, if same, then you know the other is the one (this is the only one where you wouldn't know if heavy/light), but if different, then you know whether it's heavy or light

Scenario 2
3v3 - same, so you take 2v2 from other 6
2v2 - different, so you cross-switch 2 of them and re-weigh (this should give you which one of the marbles is different and whether it's heavy/light)

Scenario 3
3v3 - different, so you take 2v2 from them
2v2 - same, then follow protocol from Scenario 1; different, then follow protocol from Scenario 2


EDIT: I still couldn't figure out that one possible outcome in Scenario 1... I'm still thinking on it.

EDIT, again: Sorry if this doesn't make any sense. I have it drawn out though. I'm definitely a visual learner...
 
man i took a sleeping pill 30 min ago and im still working on this. im gonna give up

i think dingy is right. there's one scenario of a 4v4 that wouldnt give the weight of the marble. is this a properly tested out problem?
 
I'm about to go to sleep too. Maybe that one scenario will come to me while I sleep. Good night everyone!
 
Yeah I looked at the answer. Makes sense. Mine works except for that one scenario! Darn!
 
lol you guys cheat! i've been thinking of this problem on and off since like May! Well, I mean, I thought about it for a whole night in May, then forgot about it, and just remembered it again today and is now in the process of spending another whole night on it 🙁
 
Bah. I just realized a big problem in my method. Oh how lame.
 
Here we go:

Scenario 1
3v3 - same, so take 2v2 from other 6
2v2 - same, so you know remaining 1v1 is different
1v1 - take one from the remaining set and weigh it with any of those already weighed, if same, then you know the other is the one (this is the only one where you wouldn't know if heavy/light), but if different, then you know whether it's heavy or light

Scenario 2
3v3 - same, so you take 2v2 from other 6
2v2 - different, so you cross-switch 2 of them and re-weigh (this should give you which one of the marbles is different and whether it's heavy/light)

Scenario 3
3v3 - different, so you take 2v2 from them
2v2 - same, then follow protocol from Scenario 1; different, then follow protocol from Scenario 2


EDIT: I still couldn't figure out that one possible outcome in Scenario 1... I'm still thinking on it.

EDIT, again: Sorry if this doesn't make any sense. I have it drawn out though. I'm definitely a visual learner...

Scenario 3 doesn't work out tho, if 2v2 is different, then cross switching will only allow you to narrow it down to 2. Need one more step.
 
Never thought I'd say this: but studying for Pchem tonight was FUN!:laugh:
 
Scenario 3 doesn't work out tho, if 2v2 is different, then cross switching will only allow you to narrow it down to 2. Need one more step.

Alas, this was my realization only moments ago.
 
ahhhh, my head is hurting, i'm gonna stop for now and relax, think about it later. If any of you wants to read the solution, tell me if it's solvable at least.
 
I finally just got my 1st acceptance!! now i wont feel bad if i post in here again lol. Man its finally nice to not have to worry anymore about the 5 other pending decisions i have. Who cares what happens im in at a school im happy with!!🙂. Theres no way im reading through 200 pages of this thread that i missed, but im sure you all have been accepted long before i was so congrats! I see ksmi and dw are cleaning up 🙂. 3 post-int waitlists really had me scared there for a bit.

edit: oh i forgot to say what school..it was UW Madison. And i got a kitty too for my son!! kinda random but w/e love kitties!😛

Sweet! I was really rooting for you Elijah! It's ok, I love kitties too.

the gnomes actually protest that black and white should be equal and without equality no one's really alive

WTF Gnomes? For the last 3 pages?
 
I think it's funny when people do that. This thread has existed since last January.

Just joined SDN in May. And I didn't even introduce myself. I just barged in and started posting random crap. 😀 This also seems to be the only thread that moves at a non-glacier pace late at night.
 
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