HAY GUYS

Omnislash124 · Sep 29, 2006, 07:45 AM

Originally Posted by Hotobu

I just saw this just now. I didn't look through all the solutions, but I think I've got a good idea.

(This could be done much quicker had you said if the oddball were heavier or lighter)

Pick 6 eggs at random put 3 on one scale and 3 on the other, if they balance your oddball is in the remaining three.

If the scales don't balance pick either side and balance it with the remaining three (I'll call that *3)[we also know *3 is normal]. If *3 and your remaining pick balance you know the oddball is in the one you took off if *3 and the other side don't balance you know it's in the other group.

You now are down to 3 suspects.

You take two at random and take 2 from *3 if they balance the remaning one is the oddball. If they don't then you just balance each of the two 1 - 1 with an egg from * 3.

Knowing if the egg is lighter or heavier definitely saves steps.

Actually if you do it this way and you get lucky (i.e. the 3 eggs you don't select contain the oddball and you don't way the oddball in the 2 - 2 step) this can be done in two steps. At worst you'll do 5. Knowing if the egg is lighter or heaver means that at worst it'll take 4 steps.

edit: To avoid seeing solutions I didn't see that we were assuming the oddball was heavier. Someone posted a solution for that, but my way will work even if you don't know whether or not it's lighter or heavier.

Here was mine, 3 steps at worst.

Spoiler:

There's nowhere I can't reach.

nazpyro · 11:38 AM

Originally Posted by eraemia

Try to solve this problem:

You have 9 eggs that are all of the same weight except one. How can you determine which of the eggs is the oddball by setting up only three configurations on a balance? In each configuration, all the eggs are placed simultaneously onto the balance (i.e., you cannot place the eggs one by one onto the balance).

I just also want to mention that the original problem works out better (or COOLER) if, instead of 9 eggs you have 12 eggs, all the same weight except one. Same rules apply: it could be heavier or lighter (i.e. you don't know and can't assume!), and you have to find it in 3 configurations.

So to completely restate:

You have 12 eggs that are all of the same weight except one. How can you determine which of the eggs is the oddball by setting up only three configurations on a balance? In each configuration, all the eggs are placed simultaneously onto the balance (i.e., you cannot place the eggs one by one onto the balance).

This thing is sticky, and I don't like it. I don't appreciate it.

Dekoa · Oct 5, 2006, 11:32 AM

Here is the way I would do the 9 egg problem (And this is before I read the entire thread):

Spoiler:

I think you can solve the other one that way too with a little bit of modification.

I am a dolphin, do you want me on your body?