GCD of 87, 91, 21 Calculator

Given Input numbers are 87, 91, 21

To find the GCD of numbers using factoring list out all the divisors of each number

Divisors of 87

List of positive integer divisors of 87 that divides 87 without a remainder.

1, 3, 29, 87

Divisors of 91

List of positive integer divisors of 91 that divides 91 without a remainder.

1, 7, 13, 91

Divisors of 21

List of positive integer divisors of 21 that divides 21 without a remainder.

1, 3, 7, 21

Greatest Common Divisior

We found the divisors of 87, 91, 21 . The biggest common divisior number is the GCD number.
So the Greatest Common Divisior 87, 91, 21 is 1.

Therefore, GCD of numbers 87, 91, 21 is 1

Given Input Data is 87, 91, 21

Make a list of Prime Factors of all the given numbers initially

Prime Factorization of 87 is 3 x 29

Prime Factorization of 91 is 7 x 13

Prime Factorization of 21 is 3 x 7

The above numbers do not have any common prime factor. So GCD is 1

Step1:

Let's calculate the GCD of first two numbers

The formula of GCD is GCD(a, b) = ( a x b) / LCM(a, b)

LCM(87, 91) = 7917

GCD(87, 91) = ( 87 x 91 ) / 7917

GCD(87, 91) = 7917 / 7917

GCD(87, 91) = 1

Step2:

Here we consider the GCD from the above i.e. 1 as first number and the next as 21

The formula of GCD is GCD(a, b) = ( a x b) / LCM(a, b)

LCM(1, 21) = 21

GCD(1, 21) = ( 1 x 21 ) / 21

GCD(1, 21) = 21 / 21

GCD(1, 21) = 1

GCD of 87, 91, 21 is 1

Here are some samples of GCD of Numbers calculations.

• GCD of 70, 43, 97
• GCD of 39, 76, 56
• GCD of 23, 51, 98
• GCD of 14, 62, 61
• GCD of 13, 10, 79

1. What is the GCD of 87, 91, 21?

GCD of 87, 91, 21 is 1

2. Where do I get the detailed procedure to find GCD of 87, 91, 21?

You can find a detailed procedure to find GCD of 87, 91, 21 on our page.

3. How to find GCD of 87, 91, 21 on a calculator?

You can find the GCD of 87, 91, 21 by simply giving the inputs separated by commas and click on the calculate button to avail the Greatest Common Divisor in less time.