GCF for 15, 45 and 75

"Greatest Common Factor of 3 Numbers" Calculator

What's the Greatest Common Factor (GCF) of 15, 45 and 75?

Answer

GCF of 15, 45 and 75 is

Common factors: 1, 3, 5, 15

15 divides all three: 15 ÷ 15 = 1, 45 ÷ 15 = 3, 75 ÷ 15 = 5 — and 1, 3 and 5 have no factor but 1 common to all of them, so no larger number divides all three.

15 = 3 × 5

45 = 3² × 5

75 = 3 × 5²

Prime	15	45	75	Lowest power
3	3	3²	3	3
5	5	5	5²	5

GCF = 3 × 5 = 15

More with these numbers

Related Calculations

GCF Table

1st	2nd	3rd	GCF
15	45	60	15
15	45	61	1
15	45	62	1
15	45	63	3
15	45	64	1
15	45	65	5
15	45	66	3
15	45	67	1
15	45	68	1
15	45	69	3
15	45	70	5
15	45	71	1
15	45	72	3
15	45	73	1
15	45	74	1
15	45	75	15
15	45	76	1
15	45	77	1
15	45	78	3
15	45	79	1
15	45	80	5
15	45	81	3
15	45	82	1
15	45	83	1
15	45	84	3
15	45	85	5
15	45	86	1
15	45	87	3
15	45	88	1
15	45	89	1

FAQ

What's the Greatest Common Factor (GCF) of 15, 45 and 75?

GCF of 15, 45 and 75 is 15

What prime factors do 15, 45 and 75 share?

All three factorizations contain 3 × 5, and multiplying those shared primes gives 15 — exactly the greatest common factor.

Can you get the GCF of 15, 45 and 75 two numbers at a time?

Yes. The GCF of 15 and 45 is 15, and the GCF of 15 and 75 is 15 — 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 15 : 45 : 75?

Divide every term by the GCF 15: 15 ÷ 15 = 1, 45 ÷ 15 = 3 and 75 ÷ 15 = 5. So 15 : 45 : 75 in lowest terms is 1 : 3 : 5, and no whole number other than 1 divides all three of those.

GCF for 15, 45 and 75

What's the Greatest Common Factor (GCF) of 15, 45 and 75?

More with these numbers

Related Calculations

See Also

GCF Table

FAQ

What's the Greatest Common Factor (GCF) of 15, 45 and 75?

What prime factors do 15, 45 and 75 share?

Can you get the GCF of 15, 45 and 75 two numbers at a time?

How does the GCF simplify the ratio 15 : 45 : 75?

See Also

1st	2nd	3rd	GCF
15	45	60	15
15	45	61	1
15	45	62	1
15	45	63	3
15	45	64	1
15	45	65	5
15	45	66	3
15	45	67	1
15	45	68	1
15	45	69	3
15	45	70	5
15	45	71	1
15	45	72	3
15	45	73	1
15	45	74	1
15	45	75	15
15	45	76	1
15	45	77	1
15	45	78	3
15	45	79	1
15	45	80	5
15	45	81	3
15	45	82	1
15	45	83	1
15	45	84	3
15	45	85	5
15	45	86	1
15	45	87	3
15	45	88	1
15	45	89	1

1st	2nd	3rd	GCF
15	45	60	15
15	45	61	1
15	45	62	1
15	45	63	3
15	45	64	1
15	45	65	5
15	45	66	3
15	45	67	1
15	45	68	1
15	45	69	3
15	45	70	5
15	45	71	1
15	45	72	3
15	45	73	1
15	45	74	1
15	45	75	15
15	45	76	1
15	45	77	1
15	45	78	3
15	45	79	1
15	45	80	5
15	45	81	3
15	45	82	1
15	45	83	1
15	45	84	3
15	45	85	5
15	45	86	1
15	45	87	3
15	45	88	1
15	45	89	1

1st	2nd	3rd	GCF
15	45	60	15
15	45	61	1
15	45	62	1
15	45	63	3
15	45	64	1
15	45	65	5
15	45	66	3
15	45	67	1
15	45	68	1
15	45	69	3
15	45	70	5
15	45	71	1
15	45	72	3
15	45	73	1
15	45	74	1
15	45	75	15
15	45	76	1
15	45	77	1
15	45	78	3
15	45	79	1
15	45	80	5
15	45	81	3
15	45	82	1
15	45	83	1
15	45	84	3
15	45	85	5
15	45	86	1
15	45	87	3
15	45	88	1
15	45	89	1