Solutions by everydaycalculation.com

The GCF of 20 and 90 is 10.

- Find the prime factorization of 20

20 = 2 × 2 × 5 - Find the prime factorization of 90

90 = 2 × 3 × 3 × 5 - To find the GCF, multiply all the prime factors common to both numbers:

Therefore, GCF = 2 × 5 - GCF =
**10**

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Find hcf of: 40 & 180 10 & 45 60 & 270 100 & 450 4 & 18 140 & 630 40 & 90 20 & 180 60 & 90 20 & 270 100 & 90 20 & 450 140 & 90 20 & 630

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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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