GCF for 20 and 80

"Greatest Common Factor" Calculator

Greatest Common Factor of

and

What is the Greatest common Divisor of 20 and 80?

Answer: GCF of 20 and 80 is 20

(Twenty)

Finding GCF for 20 and 80 using all factors (divisors) listing

The first method to find GCF for numbers 20 and 80 is to list all factors for both numbers and pick the highest common one:

All factors of 20: 1, 2, 4, 5, 10, 20

All factors of 80: 1, 2, 4, 5, 8, 10, 16, 20, 40, 80

So the Greatest Common Factor for 20 and 80 is 20

Finding GCF for 20 and 80 by Prime Factorization

The second method to find GCF for numbers 20 and 80 is to list all Prime Factors for both numbers and multiply the common ones:

All Prime Factors of 20: 2, 2, 5

All Prime Factors of 80: 2, 2, 2, 2, 5

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 20 and 80? (The answer is: 20). Select the first number (e.g. '20') and the second number (e.g. '80'). 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
5805
6802
7801
8808
9801
108010
11801
12804
13801
14802
15805
168016
17801
18802
19801
208020
21801
22802
23801
24808
25805
26802
27801
28804
29801
308010
31801
328016
33801
34802

FAQ

What is the Greatest common Divisor of 20 and 80?

GCF of 20 and 80 is 20

See Also