What is the greatest common factor of 42, 28, and 70
The prime factorization of 42 is 2 × 3 × 7.
The prime factorization of 28 is 2 × 2 × 7.
The prime factorization of 70 is 2 × 5 × 7.
To find the greatest common factor of the three numbers, we need to find the largest factor that all three share in common. Looking at the prime factorization, we see that they all share a factor of 2 and a factor of 7.
Thus, the greatest common factor of 42, 28, and 70 is 2 × 7 = 14.