Solutions by everydaycalculation.com

The GCF of 51 and 20 is 1.

- Find the prime factorization of 51

51 = 3 × 17 - Find the prime factorization of 20

20 = 2 × 2 × 5 - To find the GCF, multiply all the prime factors common to both numbers:

Therefore, GCF = 1

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Find hcf of: 102 & 40 153 & 60 255 & 100 357 & 140 102 & 20 51 & 40 153 & 20 51 & 60 255 & 20 51 & 100 357 & 20 51 & 140

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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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