Solutions by everydaycalculation.com

The GCF of 21 and 14 is 7.

- Find the prime factorization of 21

21 = 3 × 7 - Find the prime factorization of 14

14 = 2 × 7 - To find the GCF, multiply all the prime factors common to both numbers:

Therefore, GCF = 7

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Find hcf of: 42 & 28 63 & 42 105 & 70 147 & 98 3 & 2 42 & 14 21 & 28 63 & 14 21 & 42 105 & 14 21 & 70 147 & 14 21 & 98

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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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