What is the GCF of 28 and 12?
Greatest Common Factor is the 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 28 and 12 is 4
Two methods to find the GCF of 28 and 12 are explained below.
Methods to find GCF of 28 and 12
- Prime Factorization for GCF(28, 12)
- Long Division for GCF(28, 12)
Method 1: GCF of 28 and 12 by Prime Factorization
GCF is the product of the factors that are common to each of the given numbers.
Prime factorization of 28 is 2 × 2 × 7
Prime factorization of 12 is 2 × 2 × 3
The occurrences of common prime factors of 28 and 12 are 2 and 2
Hence GCF(28, 12) is 2 × 2 = 4
Method 2: GCF of 28 and 12 by Long Division
- Step 1: Divide the larger number by the smaller number.
- 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 28 as dividend and smaller value 12 as the divisor
We will get the GCF same for the given numbers by using different methods.