GCF of 15 and 20

What is the GCF of 15 and 20?

GCF of 15 and 20

is 5

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Greatest Common Factor

What is the Greatest Common Factor of 15 and 20? 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 15 and 20 using those formula above, step by step instructions are given below

Prime Factorization Method:

  1. Find the prime factors of the first number 15.
    3, 5
  2. Find the prime factors of the second number 20.
    2, 2, 5
  3. Multiply of all the common prime factors is the GCF value. Which is,
    5

Factors Method:

  1. Find the factors of the first number 15.
    1, 3, 5, 15
  2. Find the factors of the second number 20.
    1, 2, 4, 5, 10, 20
  3. The biggest common factor number is the GCF value. Which is,
    5

Number GCF LCM
15 & 15 15 15
15 & 16 1 240
15 & 17 1 255
15 & 18 3 90
15 & 19 1 285
15 & 20 5 60
15 & 21 3 105
15 & 22 1 330
15 & 23 1 345
15 & 24 3 120
15 & 25 5 75

GCF (Greatest Common Factor) of 15 and 20 is 5.

GCD (Greatest Common Divisor) of 15 and 20 is 5.

HCF (Highest Common Factor) of 15 and 20 is 5.
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