37.6666667
20
1,000 x 3 = 3,000
102 ÷ 3 = 34
1 goes into 81 81 times.
32
15
81 ÷ 9 = 9
75 ÷ 3 = 25
28 3s
81/7 = 11 4/7
The factors of 64 are all 2s and the factors of 81 are all 3s. The greatest common factor is 1, since they have no factors in common. ■