GCF of 21 and 30

What is the GCF of 21 and 30?

GCF of 21 and 30

is 3

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Greatest Common Factor

What is the Greatest Common Factor of 21 and 30? The greatest common factor (GCF) of a set of numbers is the largest positive integer that divides each of the numbers evenly. It's also called the greatest common divisor (GCD).

The GCF can be found using a variety of methods, including prime factorization and division. The Euclidean algorithm is a commonly used method for finding the GCF of two numbers, and it can be extended to finding the GCF of more than two numbers.

To find GCF (Greatest Common Factor) between two numbers, mainly there are two methods available, Those are-

1. Prime Factorization Method: Find the prime factors of both number and then multiply of all the common prime factors value, you will get the GCF value.

2. Factors Method: Find the factors of both number. In those both factors the highest common factor number is the GCF value.

For calculation, here's how to calculate GCF of 21 and 30 using those formula above, step by step instructions are given below

Prime Factorization Method:

  1. Find the prime factors of the first number 21.
    3, 7
  2. Find the prime factors of the second number 30.
    2, 3, 5
  3. Multiply of all the common prime factors is the GCF value. Which is,
    3

Factors Method:

  1. Find the factors of the first number 21.
    1, 3, 7, 21
  2. Find the factors of the second number 30.
    1, 2, 3, 5, 6, 10, 15, 30
  3. The biggest common factor number is the GCF value. Which is,
    3

Number GCF LCM
21 & 25 1 525
21 & 26 1 546
21 & 27 3 189
21 & 28 7 84
21 & 29 1 609
21 & 30 3 210
21 & 31 1 651
21 & 32 1 672
21 & 33 3 231
21 & 34 1 714
21 & 35 7 105

GCF (Greatest Common Factor) of 21 and 30 is 3.

GCD (Greatest Common Divisor) of 21 and 30 is 3.

HCF (Highest Common Factor) of 21 and 30 is 3.
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