9 Gram Marbles Riddle

You are given a set of scales and 12 marbles.

9 gram marbles riddle. There are three possible outcomes. Find the 9 gram marbles there are ten bags containing marbles. Nine of the bags contains only marbles weighting 10 grams each. Put 1 2 3 on the left side and 4 5 6 on the right side.

Nine marbles you have 9 marbles. In other words you get to take 2 measurements or comparisons here. The scales are of the old balance variety. Given a scale how could you tell which jar had the contaminated pills in just one measurement.

1 weighs 1 1 ounce. To find the contaminated jar follow this step wise approach. Each bag has at least 10 marbles in it. The 9 marbles are all uniform in size appearance and shape.

Lets start as always by numbering them 1 to 9. The single 9 shows up as the rightmost digit in the sum of all the weights. You must determine which of the 9 marbles is the heavier one using the balance only 2 times. You don t know which is which.

One of the bags contains only marbles weighing nine grams each. 8 of them weigh 1 ounce each. 1 you have 9 marbles as seen. Each pill weighs 10 grams except for contaminated pills contained in one jar where each pill weighs 9 grams.

Scale tilts left means the heavy coin is in group 1 2 3 scale tilts right means the heavy coin is in group 4 5 6 scale balances means the heavy coin is in group 7 8 9. In any case on to the riddle. That is a small dish hangs from each end of a rod that is balanced in the middle. So let s do this.

You have access to a balance scale containing 2 trays you may use the balance 2 times. And if the marbles on the scale do not weigh the same then we know that one of the marbles on the scale is the heaviest and we can eliminate the marbles that are not on the scale. If the number of grams ends in 8 it is the second bag with the 9 gram marbles because 2 times 9 equals 18 and that will be added to the total producing a number ending in 8. 3 you are allowed to use set the scale twice in total.

2 8 of them are exactly the same weight. We put 3 marbles on each pan for a total of 6 marbles on the pan and we leave 2 marbles off the pan. A rightmost 7 means it is the third bag with the 9 gram marbles. Here is an interesting riddle involving 12 marbles and a balance scale.