12 Marbles Brain Teaser

Can you solve this classic brain teaser.

12 marbles brain teaser.

You can perform up to a maximum of three weighings to find out which marble has the different weight and if it is heavier or lighter than the others. You are allowed to use the scales three times if you wish but no more. The heavier ball is the one you are. Here is an interesting riddle involving 12 marbles and a balance scale.

How do you find the heavier ball using the scale only three times. The emperor offers you a chance to live by playing a simple game. If they balance then the different marble is in the group 9 10 11 12. So another perfectly valid solution to the 12 marbles puzzle might even be.

First weigh 5 balls against 5 balls 1st use of scale. In general if you have n weights at your disposal you can solve the puzzle up to 3 n marbles included. Note that the unusual marble may be heavier or lighter than the others. You will be blindfolded and the bowls and marbles will be thoroughly mixed.

For the first weighing let us put on the left pan marbles 1 2 3 4 and on the right pan marbles 5 6 7 8. One of the 12 marbles is inconsistent with. Balance lets you see whether lhs is or rhs. Update i have collaborated with the talented ted ed team to bring you a fully animated version of this riddle.

There are two possibilities. You are a prisoner sentenced to death. Your task is to identify the unusual marble and discard it. He gives you 50 black marbles 50 white marbles and 2 empty bowls and instructs you to divide the 100 marbles into the two bowls.

It goes like this. Let us number the coins from 1 to 12. Either they balance or they don t. You have 12 marbles and a balance scale.

Brain teaser weighing puzzle. There are two possibilities. If the scale is equal then discard those 10 balls and weigh the remaining 2 balls against each other second use of scale. 11 identical one secretly lighter heavier.

Of the 12 balls 11 are identical and 1 weighs slightly more. So that the plan can be followed let us number the marbles from 1 to 12. 2v2 8 xy 1v1 0 z 3v3 2 xy 1v1 1 z 1v1 0 which requires only two weights in one third of the cases. If they balance then the different coin is in the group 9 10 11 12.

Continue reading for the video. The 12 marbles appear to be identical. Either they balance or they don t. We first see if such solution is feasible.

You have a balance and 12 marbles. You can divide them however you want as long as all the marbles are in the bowls. For the first weighing let us put on the left pan coins 1 2 3 4 and on the right pan coins 5 6 7 8. So for our second one possibility is to weigh 9 10 11 against 1 2 3.

Determine which marble is weird and whether it is lighter or heavier in 3 weighings. One of the 12 marbles is irregular but you don t know whether it s heavier or lighte. In fact 11 of them are identical and one is of a different weight.