100 coins in a bag in acountry where coins exist of 1,2,3,4 ,5.
Source: Swedish Mathematical Competition 2004 p2
March 21, 2021
number theory
Problem Statement
In one country there are coins of value or . Nisse wants to buy a pair of shoes. While paying, he tells the seller that he has coins in the bag, but that he does not know the exact number of coins of each value. ”Fine, then you will have the exact amount”, the seller responds. What is the price of the shoes, and how did the seller conclude that Nisse would have the exact amount?