Subtract 21/40 from 7/16
7/16 - 21/40 is -7/80.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 16 and 40 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 16 × 5 = 80,
7/16 = 7 × 5/16 × 5 = 35/80 - Likewise, for the 2nd fraction, since 40 × 2 = 80,
21/40 = 21 × 2/40 × 2 = 42/80 - Subtract the two like fractions:
35/80 - 42/80 = 35 - 42/80 = -7/80
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 14/16-21/40 7/16-42/40 7/32-21/40 7/16-21/80 21/16-21/40 7/16-63/40 7/48-21/40 35/16-21/40 7/80-21/40 49/16-21/40