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 72, 78 i.e. 6 largest integer by which both the numbers can be divided.
Greatest common factor (GCF) of 72 and 78 is 6.
GCF(72,78) = 6
Greatest common factor or Greatest common divisor (GCD) can be calculated in following way;
Prime Factorization of 72
2 | 72 |
2 | 36 |
2 | 18 |
3 | 9 |
3 | 3 |
1 |
Prime factors of 72 are 2,3. Prime factorization of 72 in exponential form is:
72 = 23×32
Prime Factorization of 78
2 | 78 |
3 | 39 |
13 | 13 |
1 |
Prime factors of 78 are 2,3,13. Prime factorization of 78 in exponential form is:
78 = 21×31×131
∴ So by taking common prime factors GCF of 72 and 78 is 6
Factors of 72
List of positive integer factors of 72 that divides 72 without a remainder.
1,2,3,4,6,8,9,12,18,24,36,72
Factors of 78
List of positive integer factors of 78 that divides 78 without a remainder.
1,2,3,6,13,26,39,78
Greatest Common Factor
We found the factors and prime factorization of 72 and 78. The biggest common factor number is the GCF number.
So the greatest common factor 72 and 78 is 6.
Also check out the Least Common Multiple of 72 and 78
(i) The GCF of 72 and 78 is associative
GCF of 72 and 78 = GCF of 78 and 72
1. What is the GCF of 72 and 78?
Answer: GCF of 72 and 78 is 6.
2. What are the Factors of 72?
Answer: Factors of 72 are 1, 2, 3, 4, 6, 8, 9, 12, 18, 24, 36, 72. There are 12 integers that are factors of 72. The greatest factor of 72 is 72.
3. What are the Factors of 78?
Answer: Factors of 78 are 1, 2, 3, 6, 13, 26, 39, 78. There are 8 integers that are factors of 78. The greatest factor of 78 is 78.
4. How to Find the GCF of 72 and 78?
Answer:
Greatest Common Factor of 72 and 78 = 6
Step 1: Find the prime factorization of 72
72 = 2 x 2 x 2 x 3 x 3
Step 2: Find the prime factorization of 78
78 = 2 x 3 x 13
Step 3: Multiply those factors both numbers have in common in steps i) or ii) above to find the gcf:
GCF = 2 x 3 = 6
Step 4: Therefore, the greatest common factor of 72 and 78 is 6