What is the GCF of 42 and 63?
Greatest Common Factor: GCF of two or more numbers is the largest number that can divide the given numbers exactly without any remainder or leaving a remainder zero.
Answer: GCF of 42 and 63 is 21
Two methods to find the GCF of 42 and 63 are explained below.
Methods to find GCF of 42 and 63
- Prime factorization Method
- Long division Method
Method1: GCF of 42 and 63 by Prime Factorization
Let us represent 42 and 63 as a product of its prime factors.
Prime factorization of 42 is 2 × 3 × 7
Prime factorization of 63 is 3 × 3 × 7
Common factors = 3 × 7
GCF is the product of the factors that are common to each of the given numbers.
GCF = 21
Method2: GCF of 42 and 63 by Long Division
- Step 1: Divide 63 by 42 and check the remainder.
- Step 2: Make the remainder of the above step as the divisor and the divisor of the above step as the dividend and perform the long division again.
- Step 3: Continue performing the division till you get remainder as zero.
You can find the GCF in any of the above methods but the solution will be the same.