GCF for 28, 42 and 70

"Greatest Common Factor of 3 Numbers" Calculator

What's the Greatest Common Factor (GCF) of 28, 42 and 70?

Answer

GCF of 28, 42 and 70 is

Common factors: 1, 2, 7, 14

14 divides all three: 28 ÷ 14 = 2, 42 ÷ 14 = 3, 70 ÷ 14 = 5 — and 2, 3 and 5 have no factor but 1 common to all of them, so no larger number divides all three.

28 = 2² × 7

42 = 2 × 3 × 7

70 = 2 × 5 × 7

Prime	28	42	70	Lowest power
2	2²	2	2	2
3	—	3	—	—
5	—	—	5	—
7	7	7	7	7

— = power 0: the prime is not a factor of this number, so it cannot be in the GCF.

GCF = 2 × 7 = 14

More with these numbers

Related Calculations

GCF Table

1st	2nd	3rd	GCF
28	42	55	1
28	42	56	14
28	42	57	1
28	42	58	2
28	42	59	1
28	42	60	2
28	42	61	1
28	42	62	2
28	42	63	7
28	42	64	2
28	42	65	1
28	42	66	2
28	42	67	1
28	42	68	2
28	42	69	1
28	42	70	14
28	42	71	1
28	42	72	2
28	42	73	1
28	42	74	2
28	42	75	1
28	42	76	2
28	42	77	7
28	42	78	2
28	42	79	1
28	42	80	2
28	42	81	1
28	42	82	2
28	42	83	1
28	42	84	14

FAQ

What's the Greatest Common Factor (GCF) of 28, 42 and 70?

GCF of 28, 42 and 70 is 14

What prime factors do 28, 42 and 70 share?

All three factorizations contain 2 × 7, and multiplying those shared primes gives 14 — exactly the greatest common factor.

Can you get the GCF of 28, 42 and 70 two numbers at a time?

Yes. The GCF of 28 and 42 is 14, and the GCF of 14 and 70 is 14 — the same answer, because the greatest common factor is associative and does not depend on the order of the three numbers.

How does the GCF simplify the ratio 28 : 42 : 70?

Divide every term by the GCF 14: 28 ÷ 14 = 2, 42 ÷ 14 = 3 and 70 ÷ 14 = 5. So 28 : 42 : 70 in lowest terms is 2 : 3 : 5, and no whole number other than 1 divides all three of those.

GCF for 28, 42 and 70

What's the Greatest Common Factor (GCF) of 28, 42 and 70?

More with these numbers

Related Calculations

See Also

GCF Table

FAQ

What's the Greatest Common Factor (GCF) of 28, 42 and 70?

What prime factors do 28, 42 and 70 share?

Can you get the GCF of 28, 42 and 70 two numbers at a time?

How does the GCF simplify the ratio 28 : 42 : 70?

See Also

1st	2nd	3rd	GCF
28	42	55	1
28	42	56	14
28	42	57	1
28	42	58	2
28	42	59	1
28	42	60	2
28	42	61	1
28	42	62	2
28	42	63	7
28	42	64	2
28	42	65	1
28	42	66	2
28	42	67	1
28	42	68	2
28	42	69	1
28	42	70	14
28	42	71	1
28	42	72	2
28	42	73	1
28	42	74	2
28	42	75	1
28	42	76	2
28	42	77	7
28	42	78	2
28	42	79	1
28	42	80	2
28	42	81	1
28	42	82	2
28	42	83	1
28	42	84	14

1st	2nd	3rd	GCF
28	42	55	1
28	42	56	14
28	42	57	1
28	42	58	2
28	42	59	1
28	42	60	2
28	42	61	1
28	42	62	2
28	42	63	7
28	42	64	2
28	42	65	1
28	42	66	2
28	42	67	1
28	42	68	2
28	42	69	1
28	42	70	14
28	42	71	1
28	42	72	2
28	42	73	1
28	42	74	2
28	42	75	1
28	42	76	2
28	42	77	7
28	42	78	2
28	42	79	1
28	42	80	2
28	42	81	1
28	42	82	2
28	42	83	1
28	42	84	14

1st	2nd	3rd	GCF
28	42	55	1
28	42	56	14
28	42	57	1
28	42	58	2
28	42	59	1
28	42	60	2
28	42	61	1
28	42	62	2
28	42	63	7
28	42	64	2
28	42	65	1
28	42	66	2
28	42	67	1
28	42	68	2
28	42	69	1
28	42	70	14
28	42	71	1
28	42	72	2
28	42	73	1
28	42	74	2
28	42	75	1
28	42	76	2
28	42	77	7
28	42	78	2
28	42	79	1
28	42	80	2
28	42	81	1
28	42	82	2
28	42	83	1
28	42	84	14