What is the greatest common factor of 42 and 98?

Answer 1

The greatest common factor of 98 and 42 is 14.

Answer 2

The greatest common factor is the highest number that divides exactly into two or more numbers.

42: 1, 2, 3, 6, 7, 14, 21, 42

98: 1, 2, 7, 14, 49, 98

The GCF of 42 and 98 is 14.
If you're not a good guesser the best way to go about doing this is to list all the factors of each number, like so:

42-- 98--

1 1

2 2

3 7

6 14

7

14

21

42

Well, I did not list all the factors of 98, but I know that since 98 is not divisible by 21 or 42 that the greatest common factor is 14.

Answer: 14