Subtract 56/15 from 20/21
1st number: 20/21, 2nd number: 3 11/15
20/21 - 56/15 is -292/105.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 15 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
20/21 = 20 × 5/21 × 5 = 100/105 - Likewise, for the 2nd fraction, since 15 × 7 = 105,
56/15 = 56 × 7/15 × 7 = 392/105 - Subtract the two like fractions:
100/105 - 392/105 = 100 - 392/105 = -292/105
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/21-56/15 20/42-56/15 20/21-56/30 60/21-56/15 20/63-56/15 20/21-56/45 20/21-56/75