GCF for 90 and 420

What is the Greatest common Divisor of 90 and 420?

Answer: GCF of 90 and 420 is 30

(Thirty)

Finding GCF for 90 and 420 using all factors (divisors) listing

The first method to find GCF for numbers 90 and 420 is to list all factors for both numbers and pick the highest common one:

All factors of 90: 1, 2, 3, 5, 6, 9, 10, 15, 18, 30, 45, 90

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 90 and 420 is 30

Finding GCF for 90 and 420 by Prime Factorization

The second method to find GCF for numbers 90 and 420 is to list all Prime Factors for both numbers and multiply the common ones:

All Prime Factors of 90: 2, 3, 3, 5

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

As we can see there are Prime Factors common to both numbers: 2, 3, 5

Now we need to multiply them to find GCF: 2 × 3 × 5 = 30

GCF Table

Number 1Number 2GCF
7542015
764204
774207
784206
794201
8042020
814203
824202
834201
8442084
854205
864202
874203
884204
894201
9042030
914207
924204
934203
944202
954205
9642012
974201
9842014
994203
10042020
1014201
1024206
1034201
1044204

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 90 and 420? (The answer is: 30). Select the first number (e.g. '90') 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

FAQ

What is the Greatest common Divisor of 90 and 420?

GCF of 90 and 420 is 30