A store has 54 green marbles, 72 yellow marbles, and 90 red marbles. The owner decides to package all the marbles into bags, such that each bag contains the same number of marbles. Additionally, each bag can only contain marbles of the same colour. Find the maximum possible number of marbles in each bag. Three wires measuring 18 m, 45 m, and 36 m are to be cut into pieces of equal length, without wastage. What is the maximum possible length of each piece?

AppendixLO1