Question

What is the greast comma factor of 21 and 40

Answer 1

1

Explanation:

you can just right down the multiples of both of the numbers then you will find the right answer

Answer 2

list the factors:

21: 1, 3, 7, 21
40: 1, 2, 4, 5, 8, 10, 20, 40

They only have 1 in common.

So 1 is the greatest common factor.