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, 15 i.e. 3 largest integer by which both the numbers can be divided.
Greatest common factor (GCF) of 12 and 15 is 3.
GCF(12,15) = 3
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 15
3 | 15 |
5 | 5 |
1 |
Prime factors of 15 are 3,5. Prime factorization of 15 in exponential form is:
15 = 31×51
∴ So by taking common prime factors GCF of 12 and 15 is 3
Factors of 12
List of positive integer factors of 12 that divides 12 without a remainder.
1,2,3,4,6,12
Factors of 15
List of positive integer factors of 15 that divides 15 without a remainder.
1,3,5,15
Greatest Common Factor
We found the factors and prime factorization of 12 and 15. The biggest common factor number is the GCF number.
So the greatest common factor 12 and 15 is 3.
Also check out the Least Common Multiple of 12 and 15
(i) The GCF of 12 and 15 is associative
GCF of 12 and 15 = GCF of 15 and 12
1. What is the GCF of 12 and 15?
Answer: GCF of 12 and 15 is 3.
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 15?
Answer: Factors of 15 are 1, 3, 5, 15. There are 4 integers that are factors of 15. The greatest factor of 15 is 15.
4. How to Find the GCF of 12 and 15?
Answer:
Greatest Common Factor of 12 and 15 = 3
Step 1: Find the prime factorization of 12
12 = 2 x 2 x 3
Step 2: Find the prime factorization of 15
15 = 3 x 5
Step 3: Multiply those factors both numbers have in common in steps i) or ii) above to find the gcf:
GCF = 3
Step 4: Therefore, the greatest common factor of 12 and 15 is 3