Question

GCF 120 using the factor tree

Answer 1

I think you need two numbers to find the greatest COMMON factor.
the factors of 120 are 1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 20, 24, 30, 40, 60 and 120

Now you just need to find the factors of the other number and see which factor is the one that they have in common and is also the biggest.

i.e. if the other number is 12. The factors are 1, 2, 3, 4, 6, and 12.
So the GCF of 120 and 12 would be 12.
Good luck!