Question

Which of the following pairs of numbers has a GCF of 1?

A. 30 and 70
B. 12 and 30
C. 16 and 21
D. 24 and 44

Answer 1

16 and 21

Explanation:

we can see

30 and 70 has 10 as factor

24 and 44 has 2 as factor

12 and 30 has 2 as factor and all those factors are greater than one

Answer 2

Explanation:

Must be 16 and 21 because we can see

30 and 70 has 10 as factor

24 and 44 has 2 as factor

12 and 30 has 2 as factor and all those factors are greater than one