Question

From the list of these numbers 3,5,7,12,15,18,20 What is a factor of 10

Answer 1

The factors of 10 are 1, 2, 5, and 10. You can also look at this the other way around: if you can multiply two whole numbers to create a third number, those two numbers are factors of the third. 2 x 5 = 10, so 2 and 5 are factors of 10.