Confusing weight
There are 8 coins in a bag. Of these coins, 7 are of equal weight. One coin weighs less than the other coins. These coins are randomly shuffled.
You have a weighing balance which tells you if one item weighs more than another item or if one item weighs less than item A or if both items are of equal weight. It does not give you the magnitude of the difference in weight between them. The weighing balance will break after it is used 2 times.
Statement- The coin that weighs less than the other coins can be isolated in less than 3 tries.
This section requires Javascript.
You are seeing this because something didn't load right. We suggest you, (a) try
refreshing the page, (b) enabling javascript if it is disabled on your browser and,
finally, (c)
loading the
non-javascript version of this page
. We're sorry about the hassle.
1 solution
True because, First divide the coins into four groups of 3, 3, 1, 1. Use your first try to compare the groups of 3 and 3 coins
Case 1: Their weight is equal In that case you are left with 2 coins and then you can easily find the lighter one.
Case 2: Their weight is unequal In that case you divide the lighter group into 3 with 1 coin each. Take any 2 coins and measure the weight. If they are unequal, then the lighter can be found easily. If they are equal then the third coin is the lightest..