Solutions by everydaycalculation.com

The GCF of 28 and 20 is 4.

- Find the prime factorization of 28

28 = 2 × 2 × 7 - 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 = 2 × 2 - GCF =
**4**

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Find hcf of: 56 & 40 14 & 10 84 & 60 140 & 100 196 & 140 56 & 20 28 & 40 84 & 20 28 & 60 140 & 20 28 & 100 196 & 20 28 & 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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