GCF for 40 and 80

"Greatest Common Factor" Calculator

Greatest Common Factor of

and

What is the Greatest common Divisor of 40 and 80?

Answer: GCF of 40 and 80 is 40

(Forty)

Finding GCF for 40 and 80 using all factors (divisors) listing

The first method to find GCF for numbers 40 and 80 is to list all factors for both numbers and pick the highest common one:

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

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

So the Greatest Common Factor for 40 and 80 is 40

Finding GCF for 40 and 80 by Prime Factorization

The second method to find GCF for numbers 40 and 80 is to list all Prime Factors for both numbers and multiply the common ones:

All Prime Factors of 40: 2, 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, 2, 5

Now we need to multiply them to find GCF: 2 × 2 × 2 × 5 = 40

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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 40 and 80? (The answer is: 40). Select the first number (e.g. '40') 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
25805
26802
27801
28804
29801
308010
31801
328016
33801
34802
35805
36804
37801
38802
39801
408040
41801
42802
43801
44804
45805
46802
47801
488016
49801
508010
51801
52804
53801
54802

FAQ

What is the Greatest common Divisor of 40 and 80?

GCF of 40 and 80 is 40

See Also