GCD of 77, 42, 20 Calculator

Given Input numbers are 77, 42, 20

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

Divisors of 77

List of positive integer divisors of 77 that divides 77 without a remainder.

1, 7, 11, 77

Divisors of 42

List of positive integer divisors of 42 that divides 42 without a remainder.

1, 2, 3, 6, 7, 14, 21, 42

Divisors of 20

List of positive integer divisors of 20 that divides 20 without a remainder.

1, 2, 4, 5, 10, 20

Greatest Common Divisior

We found the divisors of 77, 42, 20 . The biggest common divisior number is the GCD number.
So the Greatest Common Divisior 77, 42, 20 is 1.

Therefore, GCD of numbers 77, 42, 20 is 1

Given Input Data is 77, 42, 20

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

Prime Factorization of 77 is 7 x 11

Prime Factorization of 42 is 2 x 3 x 7

Prime Factorization of 20 is 2 x 2 x 5

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(77, 42) = 462

GCD(77, 42) = ( 77 x 42 ) / 462

GCD(77, 42) = 3234 / 462

GCD(77, 42) = 7

Step2:

Here we consider the GCD from the above i.e. 7 as first number and the next as 20

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

LCM(7, 20) = 140

GCD(7, 20) = ( 7 x 20 ) / 140

GCD(7, 20) = 140 / 140

GCD(7, 20) = 1

GCD of 77, 42, 20 is 1

Here are some samples of GCD of Numbers calculations.

• GCD of 47, 84, 70
• GCD of 39, 88, 75
• GCD of 75, 51, 82
• GCD of 76, 75, 34
• GCD of 92, 20, 77

1. What is the GCD of 77, 42, 20?

GCD of 77, 42, 20 is 1

2. Where do I get the detailed procedure to find GCD of 77, 42, 20?

You can find a detailed procedure to find GCD of 77, 42, 20 on our page.

3. How to find GCD of 77, 42, 20 on a calculator?

You can find the GCD of 77, 42, 20 by simply giving the inputs separated by commas and click on the calculate button to avail the Greatest Common Divisor in less time.