Respuesta :
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.
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.
Answer:
1
Step-by-step explanation:
you can just right down the multiples of both of the numbers then you will find the right answer