Subtract 63/20 from 21/24, Solve 21/24

Subtract 63/20 from 21/24

1^st number: 21/24, 2^nd number: 3 3/20

21/24 - 63/20 is -91/40.

Find the least common denominator or LCM of the two denominators:
LCM of 24 and 20 is 120

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 24 × 5 = 120,
21/24 = 21 × 5/24 × 5 = 105/120
Likewise, for the 2nd fraction, since 20 × 6 = 120,
63/20 = 63 × 6/20 × 6 = 378/120
Subtract the two like fractions:
105/120 - 378/120 = 105 - 378/120 = -273/120
After reducing the fraction, the answer is -91/40

MathStep (Works offline)

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