Created By : Jatin Gogia
Reviewed By : Rajasekhar Valipishetty
Last Updated : Apr 06, 2023
Make use of GCF Calculator to quickly find the Greatest Common Factor of numbers 12, 28 i.e. 4 largest integer by which both the numbers can be divided.
Greatest common factor (GCF) of 12 and 28 is 4.
GCF(12,28) = 4
Greatest common factor or Greatest common divisor (GCD) can be calculated in following way;
Prime Factorization of 12
2 | 12 |
2 | 6 |
3 | 3 |
1 |
Prime factors of 12 are 2,3. Prime factorization of 12 in exponential form is:
12 = 22×31
Prime Factorization of 28
2 | 28 |
2 | 14 |
7 | 7 |
1 |
Prime factors of 28 are 2,7. Prime factorization of 28 in exponential form is:
28 = 22×71
∴ So by taking common prime factors GCF of 12 and 28 is 4
Factors of 12
List of positive integer factors of 12 that divides 12 without a remainder.
1,2,3,4,6,12
Factors of 28
List of positive integer factors of 28 that divides 28 without a remainder.
1,2,4,7,14,28
Greatest Common Factor
We found the factors and prime factorization of 12 and 28. The biggest common factor number is the GCF number.
So the greatest common factor 12 and 28 is 4.
Also check out the Least Common Multiple of 12 and 28
(i) The GCF of 12 and 28 is associative
GCF of 12 and 28 = GCF of 28 and 12
1. What is the GCF of 12 and 28?
Answer: GCF of 12 and 28 is 4.
2. What are the Factors of 12?
Answer: Factors of 12 are 1, 2, 3, 4, 6, 12. There are 6 integers that are factors of 12. The greatest factor of 12 is 12.
3. What are the Factors of 28?
Answer: Factors of 28 are 1, 2, 4, 7, 14, 28. There are 6 integers that are factors of 28. The greatest factor of 28 is 28.
4. How to Find the GCF of 12 and 28?
Answer:
Greatest Common Factor of 12 and 28 = 4
Step 1: Find the prime factorization of 12
12 = 2 x 2 x 3
Step 2: Find the prime factorization of 28
28 = 2 x 2 x 7
Step 3: Multiply those factors both numbers have in common in steps i) or ii) above to find the gcf:
GCF = 2 x 2 = 4
Step 4: Therefore, the greatest common factor of 12 and 28 is 4