Question

List the factors of 15 and 30. Indicate which factors are common to both numbers and the Greatest Common Factor (GCF). 

Answer 1

Factors of 15 . . . 1, 3, 5, 15

Factors of 30 . . . 1, 2, 3, 5, 6, 10, 15, 30

Common factors (numbers on both lists) . . . 1, 3, 5, 15

Greatest common factor (biggest number on both lists) . . . 15