GCD of 81, 63, 18, 42 Calculator

Given Input numbers are 81, 63, 18, 42

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

Divisors of 81

List of positive integer divisors of 81 that divides 81 without a remainder.

1, 3, 9, 27, 81

Divisors of 63

List of positive integer divisors of 63 that divides 63 without a remainder.

1, 3, 7, 9, 21, 63

Divisors of 18

List of positive integer divisors of 18 that divides 18 without a remainder.

1, 2, 3, 6, 9, 18

Divisors of 42

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

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

Greatest Common Divisior

We found the divisors of 81, 63, 18, 42 . The biggest common divisior number is the GCD number.
So the Greatest Common Divisior 81, 63, 18, 42 is 3.

Therefore, GCD of numbers 81, 63, 18, 42 is 3

Given Input Data is 81, 63, 18, 42

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

Prime Factorization of 81 is 3 x 3 x 3 x 3

Prime Factorization of 63 is 3 x 3 x 7

Prime Factorization of 18 is 2 x 3 x 3

Prime Factorization of 42 is 2 x 3 x 7

Highest common occurrences in the given inputs are 3¹

Multiplying them we get the GCD as 3

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(81, 63) = 567

GCD(81, 63) = ( 81 x 63 ) / 567

GCD(81, 63) = 5103 / 567

GCD(81, 63) = 9

Step2:

Here we consider the GCD from the above i.e. 9 as first number and the next as 18

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

LCM(9, 18) = 18

GCD(9, 18) = ( 9 x 18 ) / 18

GCD(9, 18) = 162 / 18

GCD(9, 18) = 9

Step3:

Here we consider the GCD from the above i.e. 9 as first number and the next as 42

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

LCM(9, 42) = 126

GCD(9, 42) = ( 9 x 42 ) / 126

GCD(9, 42) = 378 / 126

GCD(9, 42) = 3

GCD of 81, 63, 18, 42 is 3

Here are some samples of GCD of Numbers calculations.

• GCD of 88, 22, 52, 13
• GCD of 35, 77, 97, 24
• GCD of 95, 26, 75, 66
• GCD of 24, 62, 55, 60
• GCD of 79, 76, 29, 87

1. What is the GCD of 81, 63, 18, 42?

GCD of 81, 63, 18, 42 is 3

2. Where do I get the detailed procedure to find GCD of 81, 63, 18, 42?

You can find a detailed procedure to find GCD of 81, 63, 18, 42 on our page.

3. How to find GCD of 81, 63, 18, 42 on a calculator?

You can find the GCD of 81, 63, 18, 42 by simply giving the inputs separated by commas and click on the calculate button to avail the Greatest Common Divisor in less time.