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The greatest common factor is the highest number that divides exactly into two or more numbers.

21: 1, 3, 7, 21

42: 1, 2, 3, 6, 7, 14, 21, 42

56: 1, 2, 4, 7, 8, 14, 28, 56

63: 1, 3, 7, 9, 21, 63

The greatest common factor for 21, 42, 56 and 63 is 7.

Q: What is the greatest common factor of 63 56 42 and 21?

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The common factors of 21 and 42 are 3, 7 and 21. The greatest common factor (GCF) is 21.

3The GCF is: 2121.The GCF is 21.

The GCF is 42.

The Greats Common Factor (GCF) is 21 63: 1,3,7,9,21,63 42: 1,2,3,67,14,21,42 21: 1,3,7,21 They all number 21 listed in there the Factors

The GCF of 42 and 86 is 2. One way to determine the common factors and greatest common factor is to find all the factors of the numbers and compare them. The factors of 42 are 1, 2, 3, 6, 7, 14, 21, and 42. The factors of 86 are 1, 2, 43, and 86. The common factors are 1 and 2. Therefore, the greatest common factor is 2.

Related questions

The common factors of 21 and 42 are 3, 7 and 21. The greatest common factor (GCF) is 21.

21 itself is the greatest common integral factor, since 21 X 2 = 42.

Since 21 is a factor of 42, it is automatically the GCF.

7 is the greatest common factor of 4942 and 21, or of 49, 42 and 21, if that is what you meant.

The GCF is 21.

It is: 21

It is: 21

The GCF (greatest common factor) would be 21.

3The GCF is: 2121.The GCF is 21.

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