Question

Find the lowest common denominator of 3/4 and 5/8

Answer 1

The lowest common denominator of 3/4 and 5/8 is the same as the least common multiple (LCM) of 4 and 8.

Multiples of 4: 4, 8, 12, 16, ...
Multiples of 8: 8, 16, 24, 32, ...

The least common multiple of 4 and 8 is 8.

The lowest common denominator of 3/4 and 5/8 is 8.

Answer 2

The least common denominator is equal to the least common multiple of the two denominators, 4 and 8.  Because 4 is a factor of 8, the LCM of these numbers is simply 8, so the least common denominator is 8.