What is the greatest common factor of 42 and 66?

Question

3
6
42
2772

Answer 1

To find the greatest common factor (GCF) of 42 and 66, we can start by finding the prime factorizations of both numbers:

• The prime factorization of 42 is: \[ 42 = 2 \times 3 \times 7 \]

• The prime factorization of 66 is: \[ 66 = 2 \times 3 \times 11 \]

To find the GCF, we identify the common prime factors:

• Both 42 and 66 have the prime factors 2 and 3 in common.

Now we multiply these common prime factors: \[ 2 \times 3 = 6 \]

Thus, the greatest common factor (GCF) of 42 and 66 is 6.

So the answer is: 6