Question

What is the greatest common factor of 90, 126, 180, and 990?

Answer 1

Step-by-step explanation:

90 = 2 * 3² * 5

126 = 2 * 3² * 7

180 = 2² * 3² * 5

990 = 2 * 3² * 5 * 11

All of the numbers have 2 and 3² in their prime factorization. Therefore the GCF is 2 * 3² = 18.