The greatest common divisor (GCD) is 24, which is the number of identical sets that can be formed.
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Euclid's algorithm has you start by finding the remainder when dividing the larger number (72) by the smaller (48). That remainder is 24. Since it divides all the numbers (48, 72, 120) evenly, it is the GCD.
Each of the 24 sets will consist of
2 blue crayons
2 green crayons
2 yellow crayons
3 red crayons
5 colored pictures
