GCF for 80 and 100

What is the Greatest Common Factor of 80 and 100?

Answer: GCF of 80 and 100 is 20

(Twenty)

Finding GCF for 80 and 100 using all factors (divisors) listing

The first method to find GCF for numbers 80 and 100 is to list all factors for both numbers and pick the highest common one:

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

All factors of 100: 1, 2, 4, 5, 10, 20, 25, 50, 100

So the Greatest Common Factor for 80 and 100 is 20

Finding GCF for 80 and 100 by Prime Factorization

The second method to find GCF for numbers 80 and 100 is to list all Prime Factors for both numbers and multiply the common ones:

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

All Prime Factors of 100: 2, 2, 5, 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 Γ— 2 Γ— 5 = 20

GCF Table

Number 1Number 2GCF
651005
661002
671001
681004
691001
70100
711001
72100
731001
741002
75100
761004
771001
781002
791001
80100
81100
821002
831001
84100
85100
861002
871001
88100
891001
90100
911001
921004
931001
941002

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 Factor of 80 and 100? (The answer is: 20). Select the first number (e.g. '80') and the second number (e.g. '100'). 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

FAQ

What is the Greatest Common Factor of 80 and 100?

GCF of 80 and 100 is 20