Subtract 21/4 from 20/15
1st number: 1 5/15, 2nd number: 5 1/4
20/15 - 21/4 is -47/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 4 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 15 × 4 = 60,
20/15 = 20 × 4/15 × 4 = 80/60 - Likewise, for the 2nd fraction, since 4 × 15 = 60,
21/4 = 21 × 15/4 × 15 = 315/60 - Subtract the two like fractions:
80/60 - 315/60 = 80 - 315/60 = -235/60 - After reducing the fraction, the answer is -47/12
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/15-21/4 20/15-42/4 20/30-21/4 20/15-21/8 60/15-21/4 20/15-63/4 20/45-21/4 20/15-21/12 20/75-21/4 20/15-21/20 20/15-21/28