GCF of 15, 56, 42, 69

Given numbers are 15, 56, 42, 69
The greatest common factor of 15, 56, 42, 69 can be found by using the following 2 different methods.
The GCF of 15, 56, 42, 69 is 1.

Prime factorization is basically division by prime numbers only. Keep dividing all numbers by the same prime number, until the numbers can no longer be divided by a single prime number. Then, multiply all the prime numbers that are on the left side.

∴ GCF of numbers is 1 because of no common factors present between them.

The common factor method requires listing down all the factors of 15,56,42,69 that divide each of these numbers without leaving a remainder. To begin, let us list down the factors

list down the factors of 15

1,3,5,15

list down the factors of 56

1,2,4,7,8,14,28,56

list down the factors of 42

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

list down the factors of 69

1,3,23,69

Greatest Common Factor

Once you have listed down the factors, all you have to do is look for the highest factor that appears in all the three aforementioned lists. The greatest number that we can see in all lists is 1 . Therefore, the GCF of 15,56,42,69 is 1

1. What is the GCF of 15, 56, 42, 69 ?

Answer: GCF of 15, 56, 42, 69 is 1.

2. How to calculate the GCF of 15, 56, 42, 69 ?

Answer: You can use two different methods: listing down the factors, and prime factorization. If you want to use the listing method, then simply write down all the factors of 15, 56, 42, 69. Then, select the greatest number that appears in lists. From this, you will see that the GCF is 1. Next, you can also use the prime factorization method to divide the numbers by prime numbers. Then, multiply the prime numbers on the side to get your answer, which is 1.