What is the GCF of 30 and 70?
GCF (Greatest Common Factor) of two numbers is the largest possible number that divides the two numbers exactly without any remainder.
Answer: GCF of 30 and 70 is 10
Let us see how to find the GCF of 30 and 70
Explanation:
We will explain the GCF of 30 and 70 using the following two methods.
GCF of 30 and 70 by Long Division
Step 1: Divide the larger number 70 by the smaller 30 and check the remainder. Here, the remainder is 10
Step 2: Make the remainder 10 as the divisor and the divisor 30 as the dividend and perform the long division again.
Step 3: Continue till you get the remainder as 0 and GCF of 30 and 70 is the last divisor obtained.

GCF of 30 and 70 by Prime Factorization
Let us represent 30 and 70 as a product of its prime factors.
Prime factorization of 30 is 2 × 3 × 5
Prime factorization of 70 is 2 × 5 × 7
The common prime factors are 2 and 5
GC(30,70)F is the product of the prime factors that are common to 30 and 70.
GCF of 30 and 70 is 10
You can find the GCF in any of the above methods but the solution will be the same.