Answers

The gcf of 9 and 20 is 1.

Steps to find GCF

1. Find the prime factorization of 9
   9 = 3 × 3
2. Find the prime factorization of 20
   20 = 2 × 2 × 5
3. To find the gcf, multiply all the prime factors common to both numbers:
   
   Therefore, GCF = 1

The greatest common factor (gcf) is also known as greatest common divisor (gcd) or highest common factor (hcf).

Related

Find hcf of: 18 & 40 27 & 60 45 & 100 63 & 140 18 & 20 9 & 40 27 & 20 9 & 60 45 & 20 9 & 100 63 & 20 9 & 140

GCF Calculator

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