Greatest Common Factor of 28 and 19

GCF(28, 19) = 1, Greatest common factor of 28 and 19 is 1. Greatest Common Factor or Greatest Common Divisor of two numbers is the largest integer by which both the numbers can be divided. There are two different methods to calculate Greatest Common Factor of 28 and 19. Greatest Common Factor by prime factorization method and Greatest Common Factor by matching factors method.

Greatest Common Factor of 28 and 19 by prime factorization method

We will first find the prime factorization of 28 and 19.
Prime Factorization of 28 is 1, 2, 2, 7 and Prime Factorization of 19 is 1, 19.

  • Factorize\( (28) = \) \(1\times 2\times 2\times 7\)
  • Factorize\( (19) = \) \(1\times 19\)
Now we need to find any which are common for each number (1, 1) and multiply these numbers together.
\(GCF(28, 19) = 1\times 1 = 1\).

Greatest Common Factor of 28 and 19 by matching factors method

List of positive integers factors of 28 leaving a remainder zero is 1, 2, 4, 7, 14, 28
List of positive integers factors of 19 leaving a remainder zero is 1, 19
As you can see, 1 is the greatest and common number that 28 and 19 divides into.
So the greatest common factor 28 and 19 is 1.
\(GCF(28, 19) = 1\).

If you want to learn more about greatest common divisor, take a look at the Wikipedia page.
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