Subtract 8/24 from 15/21, Solve 15/21

Subtract 8/24 from 15/21

15/21 - 8/24 is 8/21.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 24 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 21 × 8 = 168,
15/21 = 15 × 8/21 × 8 = 120/168
Likewise, for the 2nd fraction, since 24 × 7 = 168,
8/24 = 8 × 7/24 × 7 = 56/168
Subtract the two like fractions:
120/168 - 56/168 = 120 - 56/168 = 64/168
After reducing the fraction, the answer is 8/21

MathStep (Works offline)

Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad