Find the gcf of 12 and 45

gcf = 3

the factors of 12 are 1, 2, 3, 4, 6 and 12

the factors of 45 are 1, 3, 5, 9, 15 and 45

the greatest common factor of 12 and 45 is 3

Step one: find the prime factorization of 12

12 = 2 x 2 x 3

Step two: fine the prime factorization of 45

45 = 3 x 3 x 5

Step three: to find the GCF, multiply all the prime factors common to both numbers:

Therefore, GCF is 3