45

81

45

81

45÷3

81÷3

15

27

15÷3

27÷3

5

9

or

45

81

3 × 3 × 5

3 × 3 × 3 × 3

5

9

or

Common Divisors for 45 and 81 are: 3 and 3

Greatest Common Divisor = 3 × 3 = 9

45÷9

81÷9

5

9

See 5/9 as a percent