Multiples of 18: 18 36 54 72 90 ...

Multiples of 24: 24 48 72 95 ...

∴ the least common denominator is 72.

You can find an answer using prime factors:

18 = 2*3*3 = 2*3

24 = 2*2*2*3 = 2

∴ the least common multiple is 2

Multiples of 24: 24 48 72 95 ...

∴ the least common denominator is 72.

You can find an answer using prime factors:

18 = 2*3*3 = 2*3

^{2}24 = 2*2*2*3 = 2

^{3}*3∴ the least common multiple is 2

^{3}*3^{2}= 72