GCD Formula

About GCD Formula

The greatest common divisor (GCD) of two numbers is the largest number that divides them exactly.
The following are the attributes of GCD:

GCD divides two or more numbers evenly without leaving a remainder.
A factor of each number is the GCD of two or more numbers.
When two or more integers are added together, the GCD is always less than or equal to each of the numbers.
When there are two or more prime numbers, the GCD is always 1.

There are three ways to find the GCD of two numbers:

Example: What is the GCD of 30 and 42?

Sol: List the factors of each number.

Factors of 30 - 1, 2, 3, 5, 6, 10, 15, 30

Factors of 42 - 1, 2, 3, 6, 7, 14, 21, 42

6 is the common factor and the greatest one.

Hence, the GCD of 30 and 42 is 6.

Answer: GCD of 30 and 42 is 6.

Get the list of all Maths formulas used in general calculations.