An interesting problem about weighing coins
Source: Iran Third Round MO 1997, Exam 1, P3
June 30, 2012
combinatorics unsolvedcombinatorics
Problem Statement
There are bags and there are similar coins in each bag (coins in each bag are similar, coins of different bags can be different). The weight of each coin is an one digit number in grams. We have a digital scale which can weigh at most grams in each weighing. Using this scale, we want to find the weight of coins of each bag.(a) Show that this operation is possible by times of weighing, and(b) It's not possible by times of weighing.