What is the greatest common factor of 20 and 30? Enter your answer in the box.

10

Step-by-step explanation:

The greatest common factor (gcf) of two number (for integers), is the largest positive number that divides each one of them.

20 = 20 x 1 = 10 x 2 = 4 x 5

30 = 30 x 1 = 15 x 2 = 10 x 3 = 6 x 5

So listing every factor of each number we get

For 20, the factors are 1 - 2 - 4 - 5 - 10 - 20

For 30, the factors are 1 - 3 - 5 - 6 - 10 - 15 - 30

As I highlighted up there, the common factor of 20 and 30 are 1 - 5 - 10.

Comparing them, we can see that 1 < 5 < 10

So, the greatest common facto of 20 and 30 is 10

The greatest common factor is 10.