GCF for 100 and 820

What is the Greatest Common Factor of 100 and 820?

Answer: GCF of 100 and 820 is 20

(Twenty)

Finding GCF for 100 and 820 using all factors (divisors) listing

The first method to find GCF for numbers 100 and 820 is to list all factors for both numbers and pick the highest common one:

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

All factors of 820: 1, 2, 4, 5, 10, 20, 41, 82, 164, 205, 410, 820

So the Greatest Common Factor for 100 and 820 is 20

Finding GCF for 100 and 820 by Prime Factorization

The second method to find GCF for numbers 100 and 820 is to list all Prime Factors for both numbers and multiply the common ones:

All Prime Factors of 100: 2, 2, 5, 5

All Prime Factors of 820: 2, 2, 5, 41

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

GCF Table

Number 1Number 2GCF
858205
868202
878201
888204
898201
9082010
918201
928204
938201
948202
958205
968204
978201
988202
998201
10082020
1018201
1028202
1038201
1048204
1058205
1068202
1078201
1088204
1098201
11082010
1118201
1128204
1138201
1148202

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 100 and 820? (The answer is: 20). Select the first number (e.g. '100') and the second number (e.g. '820'). 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 100 and 820?

GCF of 100 and 820 is 20