What is the greatest common factor of 22 and 66?

The greatest common factor of 22 and 66 can be done in a split second.

I am assuming the person who asked this question knew that 2 x 3 = 6.

Multiplication works in your favor. When doing 22 x 3, You do 2x 3, and then

2x 3 again, thus getting 66. The answer is therefore 22.