A factor is defined as "a number or quantity that when multiplied with another produces a given number or expression." For example, the factors of 20 are 1, 2, 4, 5, 10, and 20.
When we multiply 2 and 5 together, we get 10. Multiplying this by anything else besides 0 will still yield something that has 2 and 5 as factors, for example 2 times 5 times 3 is 30. As this is just the same thing as multiplying 10 by 3, the answer is any multiple of 10.
