Solutions by everydaycalculation.com

The GCF of 20 and 9 is 1.

- Find the prime factorization of 20

20 = 2 × 2 × 5 - Find the prime factorization of 9

9 = 3 × 3 - To find the GCF, multiply all the prime factors common to both numbers:

Therefore, GCF = 1

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

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The greatest common factor (GCF) is also known as greatest common divisor (GCD) or highest common factor (HCF).

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