Balance Beam Scale Riddle 7 Marbles

Split the marbles into 3 groups with 4 marbles each.

Balance beam scale riddle 7 marbles. Weigh 7 vs 8 if they balance then 4 is the odd light ball or the heaviest of 7 vs 8 is the odd heavy ball. 1 you have 9 marbles as seen. The scales are of the old balance variety. These differ from puzzles that assign weights to items in that only the relative mass of these items is relevant.

In any case on to the riddle. If 3 6 12 is heavy then either 6 is the odd heavy ball or 1 or 2 is the odd light ball. A real weight balance or scale looks slightly like the apparatus i drew above. You are given a set of scales and 12 marbles.

You can put things in the little buckets and the scale will tip to the heavier side. If 1 2 5 vs 3 6 12 balances then either 4 is the odd light ball or 7 or 8 is the odd heavy ball. 2 8 of them are exactly the same weight. If it s not completely clear how we can make the assumption that the bad coins is in group 7 8 9 when the scales balance remember we know there is a bad coin there has to be we have eliminated the other two.

Scale balances means the heavy coin is in group 7 8 9 using one weighing we have successfully narrowed three groups down to one. That is a small dish hangs from each end of a rod that is balanced in the middle. Yeah i probably shouldn t have even bothered with the picture.