Greatest Common Divisor of a Set of Numbers

Consider the number set {12, 15, 20, 25, 30}. Determine the greatest common divisor (GCD) of this set. Recall that the GCD is the largest positive integer that divides each of the numbers in the set without leaving a remainder.

To find the GCD, you may want to break down each number into its prime factors. For instance:

12 = $2^2 \times 3$

15 = $3 \times 5$

20 = $2^2 \times 5$

25 = $5^2$

30 = $2 \times 3 \times 5$