A1. In a bag, there are 26 euro coins. If I take 20 coins out of the bag, then there is at least one 1-cent coin. There are also at least two 2-cent coins and at least five 5-cent coins.

How much are the 26 coins in the bag worth in total?
A1. At least one euro cent in every grab of 20 coins means there must be at least 7 euro cents among the 26 coins. At least two 2-euro cent coins in every grab of 20 coins means at least 8 coins of 2 euro cents among the 26, and finally, five 5-euro cent coins means at least 11 coins of 5 euro cents among the 26 coins. Since there are 26 coins in total, there must be exactly seven 1-cent coins, eight 2-cent coins, and eleven 5-cent coins. Together, they are worth 78 euro cents.