GCF of 220 and 420 (Greatest Common Factor)

"Greatest Common Factor" Calculator

Greatest Common Factor of

and

What is the Greatest Common Divisor of 220 and 420?

Answer

GCF of 220 and 420 is
20

(Twenty)

Finding GCF for 220 and 420 using all factors (divisors) listing

The first method to find GCF for numbers 220 and 420 is to list all factors for both numbers and pick the highest common one:

All factors of 220: 1, 2, 4, 5, 10, 11, 20, 22, 44, 55, 110, 220

All factors of 420: 1, 2, 3, 4, 5, 6, 7, 10, 12, 14, 15, 20, 21, 28, 30, 35, 42, 60, 70, 84, 105, 140, 210, 420

So the Greatest Common Factor for 220 and 420 is 20

Finding GCF for 220 and 420 by Prime Factorization

The second method to find GCF for numbers 220 and 420 is to list all Prime Factors for both numbers and multiply the common ones:

All Prime Factors of 220: 2, 2, 5, 11

All Prime Factors of 420: 2, 2, 3, 5, 7

As we can see there are Prime Factors common to both numbers: 2, 2, 5

Now we need to multiply them to find GCF: 2 × 2 × 5 = 20

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About "Greatest Common Factor" Calculator

This calculator will help you find the greatest common factor (GCF) of two numbers. For example, it can help you find out what is the Greatest Common Divisor of 220 and 420? (The answer is: 20). Select the first number (e.g. '220') and the second number (e.g. '420'). After that hit the 'Calculate' button.
Greatest Common Factor (GCF) also known as the Greatest Common Divisor (GCD) or Highest Common Factor (HCF) - it is the largest positive integer that divides each of the integers with zero remainder.
"Greatest Common Factor" Calculator

Greatest Common Factor of

and

GCF Table

Number 1Number 2GCF
2204055
2204062
22040711
2204084
2204091
22041010
2204111
2204124
2204131
2204142
2204155
2204164
2204171
22041822
2204191
22042020
2204211
2204222
2204231
2204244
2204255
2204262
2204271
2204284
22042911
22043010
2204311
2204324
2204331
2204342

FAQ

What is the Greatest Common Divisor of 220 and 420?

GCF of 220 and 420 is 20

How to find the GCF of 220 and 420?

You can find the GCF of 220 and 420 by listing all factors of both numbers and picking the greatest common one, or by prime factorization. The GCF of 220 and 420 is 20.

What prime factors do 220 and 420 share?

The prime factorizations of 220 and 420 have 2 × 2 × 5 in common, and multiplying those shared primes gives 20 — exactly the greatest common factor.

How does the GCF reduce the fraction 220/420?

Divide the numerator and the denominator by the GCF 20: 220 ÷ 20 = 11 and 420 ÷ 20 = 21. So 220/420 in lowest terms is 11/21.

See Also