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 1215, 1220 i.e. 5 largest integer by which both the numbers can be divided.
Greatest common factor (GCF) of 1215 and 1220 is 5.
GCF(1215,1220) = 5
Greatest common factor or Greatest common divisor (GCD) can be calculated in following way;
Prime Factorization of 1215
3 | 1215 |
3 | 405 |
3 | 135 |
3 | 45 |
3 | 15 |
5 | 5 |
1 |
Prime factors of 1215 are 3,5. Prime factorization of 1215 in exponential form is:
1215 = 35×51
Prime Factorization of 1220
2 | 1220 |
2 | 610 |
5 | 305 |
61 | 61 |
1 |
Prime factors of 1220 are 2,5,61. Prime factorization of 1220 in exponential form is:
1220 = 22×51×611
∴ So by taking common prime factors GCF of 1215 and 1220 is 5
Factors of 1215
List of positive integer factors of 1215 that divides 1215 without a remainder.
1,3,5,9,15,27,45,81,135,243,405,1215
Factors of 1220
List of positive integer factors of 1220 that divides 1220 without a remainder.
1,2,4,5,10,20,61,122,244,305,610,1220
Greatest Common Factor
We found the factors and prime factorization of 1215 and 1220. The biggest common factor number is the GCF number.
So the greatest common factor 1215 and 1220 is 5.
Also check out the Least Common Multiple of 1215 and 1220
(i) The GCF of 1215 and 1220 is associative
GCF of 1215 and 1220 = GCF of 1220 and 1215
1. What is the GCF of 1215 and 1220?
Answer: GCF of 1215 and 1220 is 5.
2. What are the Factors of 1215?
Answer: Factors of 1215 are 1, 3, 5, 9, 15, 27, 45, 81, 135, 243, 405, 1215. There are 12 integers that are factors of 1215. The greatest factor of 1215 is 1215.
3. What are the Factors of 1220?
Answer: Factors of 1220 are 1, 2, 4, 5, 10, 20, 61, 122, 244, 305, 610, 1220. There are 12 integers that are factors of 1220. The greatest factor of 1220 is 1220.
4. How to Find the GCF of 1215 and 1220?
Answer:
Greatest Common Factor of 1215 and 1220 = 5
Step 1: Find the prime factorization of 1215
1215 = 3 x 3 x 3 x 3 x 3 x 5
Step 2: Find the prime factorization of 1220
1220 = 2 x 2 x 5 x 61
Step 3: Multiply those factors both numbers have in common in steps i) or ii) above to find the gcf:
GCF = 5
Step 4: Therefore, the greatest common factor of 1215 and 1220 is 5