Use the lists of common factors to answer the question FACTORS OF 9: 1,3,9

FACTORS OF 15: 1,3,5,15

FACTORS OF 21: 1,3,7,21

FACTORS OF 40: 1,2,4,5,10,20,40

Which pairs of numbers are relatively prime? check all that apply.

9 and 15

9 and 40

9 and 21

15 and 21

21 and 40

9 and 40

21 and 40

Step-by-step explanation:

I just did the test on edg. 2020

Factors of 9:

1,3,9

Factors of 15:

1,3,5,15

Factors of 21:

1,3,7,21

Factors of 40:

1,2,4,5,8,10,20,40

We have to find the pairs of numbers which are relatively prime.

Relatively prime number: The numbers in which gcd 1 are called relative prime numbers.

a.9 and 15

GCD(9,15)=3

9 and 15 are not relatively prime.

b.9 and 40

GCD(9,40)=1

Hence, 9 and 40 are relatively prime.

c.9 and 21

GCD(9,21)=3

9 and 21 are not relatively prime.

d.15 and 21

GCD(15,21)=3

15 and 21  are not relatively prime.

e.21 and 40

GCD(21,40)=1

21 and 40 are relatively prime.

3030 ur welcome

step-by-step explanation: