What is the greatest common factor for 12 and 20 and 36

Well I don't know!

Let's find it together:

The factors of 12 are 1, 2, 3, 4, 6, and 12.

The factors of 20 are 1, 2, 4, 5, 10, and 20.

The factors of 36 are 1, 2, 3, 4, 6, 9, 12, 18, and 36.

The common factors of 12, 20, and 36 (the ones that

show up on all three lists) are ...

1, 2, and 4.

The greatest one of these is 4.

Its 3 and 4 i checked on class