What is the least common factor of 8 and 20?

Answer 1

4 is the greatest common factor.

The least common multiplier (least common factor) of 8 and 20 is 40.

To solve for this you need to find the prime factors of each number

8 is 2x2x2

20 is 2x2x5

then count how many times each number is used in each set

8 has 3 twos

20 has 2 twos and 1 five

if the same number is used in both numbers throw out the repeat numbers from the smaller set

8 has more twos than 20 does, throw out the 2 twos

multiple all remaining numbers together

2x2x2x5=40

Check your work by dividing each number into your result, both should divide into it evenly

40/8=5

40/20=2

40 is the lowest number that both the 8 and the 20 will go into evenly.

Answer 2

The LCF is 1.

The GCF is 4.

The LCM is 40.

The GCM is infinite.