What is the GCF of 12 and 15?
Greatest Common Factor is a greatest number that is a factor of two or more other numbers.
The GCF (greatest common factor) is the same as: HCF (Highest Common Factor), GCD (Greatest Common Divisor), HCD (Highest Common Divisor), GCM (Greatest Common Measure), HCM (Highest Common Measure)
Answer: GCF of 12 and 15 is 3
Two methods to find the GCF of 12 and 15 are explained below.
Methods to find GCF of 12 and 15
Prime factorization Method
Method1: GCF of 12 and 15 by Prime Factorization
GCF is the product of the factors that are common to each of the given numbers.
Prime factorization of 12 is 2 × 2 × 3
Prime factorization of 15 is 3 × 5
The occurrences of common prime factors of 12 and 15 is 3
Hence GCF(12, 15) = 3
Method2: GCF of 12 and 15 by Long Division
- Step 1: Divide the larger number by the smaller
- Step 2: Divide the dividend by the remainder obtained in step 1 and repeat this step until we get the remainder as 0
- Step 3: The last dividend is the GCF of the two numbers
We take the larger value 18 as dividend and smaller value 14 as divisor
We will get the GCF same for the given numbers by using different methods.