What is the greatest common factor of 20 88 and 165?

Factor of 20 : 1,2,4,5,10,20

Factors of 88 : 1,2,4,8,11,22,44,88

Factors of 165, 1,3,5,11,15,33,55, 165

so the greast common factor is 1

The gcf is 1.