The Official IQ Questions Thread - Please do not use the internet for answers

 

There is a weighing balance and 12 balls. The 12 balls all look the same from the outside, but 1 weighs a little different from the other 11.

Using the weighing balance not more than 3 times, find out which is the odd ball and whether it is lighter or heavier :P

 

Edit: I obviously have forgotten to state that forum trolls aren't welcome

attach to ur own balls and see if tear or not

bus 555 is standing behind Daisuke-kun and Daisuki-kun is standing behing bus 555, and idea how???

Originally posted by Daisuke-kun:

attach to ur own balls and see if tear or not

KNs use own balls!!

later no more balls liow..!..

then use marbles to replace..!

Originally posted by SBS n SMRT:

bus 555 is standing behind Daisuke-kun and Daisuki-kun is standing behing bus 555, and idea how???

because Daisuke-kun and Daisuki-kun are 2 different people

Put all 12 balls on the weighing balance, get the total weight, then take out each ball from the weighing balance one at a time.

By doing so, you will be able to get the weight of each removed balls from the weight difference in the before removing and after removing each balls.

So you will be able to know which ball weigh different from the rest.

 

But why need to use the weight balance for more than 3 times? 1 time enough le......

put 6 balls a side, the heavier one is what we want.

divide the heavier group into 2 groups of 3.

den weigh again, and there'll be a heavier side again.

den from that side, pick 2 random balls and weigh them against each other.

if 2 same weight, the one left behind heavier lo.

if 2 no same weight, den obviously the heavier one is there.

hurhur

Originally posted by ChoCoChips:

put 6 balls a side, the heavier one is what we want.

divide the heavier group into 2 groups of 3.

den weigh again, and there'll be a heavier side again.

den from that side, pick 2 random balls and weigh them against each other.

if 2 same weight, the one left behind heavier lo.

if 2 no same weight, den obviously the heavier one is there.

hurhur

Clap hands...

Originally posted by MohamedF:

Clap hands...

thank you thank you

got prize anot?

Originally posted by ChoCoChips:

thank you thank you

got prize anot?

but if the heavier one is on the weighing scale with the other, can you identify which is the heavier one?

Originally posted by ChoCoChips:

thank you thank you

got prize anot?

How to send you over the net

Originally posted by Chris1988:

but if the heavier one is on the weighing scale with the other, can you identify which is the heavier one?

eh i dunno abt u la but i ish use eyes see which one is lower.

because the lower one is obviously the heavier one?!

hmmm.. any weighing expert care to shed some light?

Originally posted by ChoCoChips:

eh i dunno abt u la but i ish use eyes see which one is lower.

because the lower one is obviously the heavier one?!

hmmm.. any weighing expert care to shed some light?

solli i thought is use weighing machine. if its a weighing scale i think you're right

Originally posted by ChoCoChips:

thank you thank you

got prize anot?

I onli audience... but I gib u present aniways...

Originally posted by Chris1988:

solli i thought is use weighing machine. if its a weighing scale i think you're right

i oso scared i wrong

hurhur

let's up the question...

if there is 27 balls, and only 1 of them is heavier by 1 gram, the rest all the same weight, how do you see which ball is heavier by using a balance scale 3 times only?

Originally posted by skythewood:

let's up the question...

if there is 27 balls, and only 1 of them is heavier by 1 gram, the rest all the same weight, how do you see which ball is heavier by using a balance scale 3 times only?

is there a logical answer to this?

Originally posted by parn:

Put all 12 balls on the weighing balance, get the total weight, then take out each ball from the weighing balance one at a time.

By doing so, you will be able to get the weight of each removed balls from the weight difference in the before removing and after removing each balls.

So you will be able to know which ball weigh different from the rest.

 

But why need to use the weight balance for more than 3 times? 1 time enough le......

By weighing balance, I meant a non electronic scale (imagine the see-saw)

And also, by removing any ball from the balance, it automatically counted as another usage on the balance.

yes, if you think about it.

reveal the answer later.. but i think Choco knows the answer already

shit if i dunno the answer does it mean i low iq

Originally posted by ChoCoChips:

put 6 balls a side, the heavier one is what we want.

divide the heavier group into 2 groups of 3.

den weigh again, and there'll be a heavier side again.

den from that side, pick 2 random balls and weigh them against each other.

if 2 same weight, the one left behind heavier lo.

if 2 no same weight, den obviously the heavier one is there.

hurhur

Wrong. Firstly, you don't know if the odd ball is lighter or heavier, so you wouldn't know which group of 6 does the odd ball belongs to.

And if we were to use your method and weigh 2 random balls out of the final 3 - we still wouldn't know which is the odd ball... Simply because.. WE DON'T KNOW IF THE ODD BALL IS LIGHTER OR HEAVIER!

 

Edit: But still good attempt there, I guessed the exact same thing as you when I first chanced upon this question

Originally posted by skythewood:

yes, if you think about it.

reveal the answer later.. but i think Choco knows the answer already

i where got so smart

hurhur

Originally posted by Detached:

Wrong. Firstly, you don't know if the odd ball is lighter or heavier, so you wouldn't know which group of 6 does the odd ball belongs to.

And if we were to use your method and weigh 2 random balls out of the final 3 - we still wouldn't know which is the odd ball... Simply because.. WE DON'T KNOW IF THE ODD BALL IS LIGHTER OR HEAVIER!

oh ya hor.

weighs a lil different!

aiyo!

wait ar.

lemme think abt it and fine tune my ans

divide the 27 balls into 3 groups, A, B, C

Step 1: compare group A & group B

results/conclusion: if A is heavier. the heavier ballis in set A.

                                if B is heavier. the heavier ballis in group B.

                                If A and B same weight, ball is in group C.

divide the group with heavier ball into 3 sets, A, B, C

Step 2: compare set A & set B

results/conclusion: if A is heavier. the heavier ballis in

group A.

                                if B is heavier. the heavier ballis in set B.

                                If A and B same weight, ball is in set C.

divide the set with heavier ball into 3 balls, A, B, C

Step 3: compare ball A & ball B

results/conclusion: if A is heavier. the heavier ballis in ball A.

                                if B is heavier. the heavier ballis in ball B.

                                If A and B same weight, ball is in ball C.

 

im thinking abt grps of 4 one.

1st group against 2nd group, den 3rd group. from there can see which one heavier/lighter.

den from that group take 2 against 2.

but i'll need more than 3 tries.

tsk tsk tsk