Subtract 21/56 from 7/21
7/21 - 21/56 is -1/24.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 56 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 21 × 8 = 168,
7/21 = 7 × 8/21 × 8 = 56/168 - Likewise, for the 2nd fraction, since 56 × 3 = 168,
21/56 = 21 × 3/56 × 3 = 63/168 - Subtract the two like fractions:
56/168 - 63/168 = 56 - 63/168 = -7/168 - After reducing the fraction, the answer is -1/24
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 14/21-21/56 7/21-42/56 7/42-21/56 7/21-63/56 7/63-21/56 35/21-21/56 49/21-21/56