What is the GCF and LCM of 42 63 and 78?

Answer 1

By using prime factorization.

2 x 2 x 2 x 2 x 2 x 2 = 64

2 x 2 x 2 x 2 x 3 x 5 = 240

Select the common factors.

2 x 2 x 2 x 2 = 16, the GCF

Combine the factors, eliminating duplicates.

2 x 2 x 2 x 2 x 2 x 2 x 3 x 5 = 960, the LCM

Answer 2

Factor them.

2 x 7 = 14

2 x 3 x 7 = 42

2 x 3 x 11 = 66

Select the common factor.

The GCF is 2.

Combine the factors, eliminating duplicates.

2 x 3 x 7 x 11 = 462, the LCM

Answer 3

The GCF is: 6.

Answer 4

Gcf: 3

lcm: 1638