# What is the GCF of 15 and 45?

The GCF of two natural numbers x and y is the largest possible number which divides both x and y.

## Answer: GCF of 15 and 45 is 15

Let's find the GCF of 15 and 45

## Explanation:

We can find the GCF by the following methods

### GCF of 15 and 45 by Prime Factorization

Let us represent 15 and 45 as a product of their prime numbers:

Prime factorization of 15 is 3 x 5

Prime factorization of 45 is 3 x 3 x 5

Common factors = 3, 5

GCF is the product of the factors that are common to each of the given numbers.

GCF is 3 × 5 = 15

### GCF of 15 and 45 by Long Division Method

- Step 1: Divide 45 by 15 and check the remainder.
- Step 2: Taking the remainder of the above step as the divisor and the divisor of the above step as the dividend, perform the long division again.
- Step 3: Continue until the remainder becomes 0.