Question

which is the greatest common divisor of 72 ,81 and 180?​

Answer 1

Find the prime factorization of 72
72 = 2 × 2 × 2 × 3 × 3

Find the prime factorization of 180
180 = 2 × 2 × 3 × 3 × 5

To find the gcf, multiply all the prime factors common to both numbers:

Therefore, GCF = 2 × 2 × 3 × 3

GCF = 36

Answer 2

9 is gcd of 72,81,180