What is the HCF of 66 and 54?

Answer 1

Definition: A factor is a divisor - a number that will evenly divide into another number. The greatest common factor of two or more numbers is the largest factor that both numbers have in common.

Method:
One way to determine the common factors and greatest common factor is to find all the factors of the numbers and compare them.
The factors of 66 are 1, 2, 3, 6, 11, 22, 33, and 66.
The factors of 72 are 1, 2, 3, 4, 6, 8, 9, 12, 18, 24, 36, and 72.
The common factors are 1, 2, 3, and 6. Therefore, the greatest common factor is 6.

Answer 2

54 = 1, 4, 5, 9, 15, 24, 54

66 = 1, 6, 16, 36, 66

h(g)cf = 1