Subtract 56/7 from 40/21
1st number: 1 19/21, 2nd number: 8 0/7
40/21 - 56/7 is -128/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 7 is 21
Next, find the equivalent fraction of both fractional numbers with denominator 21 - For the 1st fraction, since 21 × 1 = 21,
40/21 = 40 × 1/21 × 1 = 40/21 - Likewise, for the 2nd fraction, since 7 × 3 = 21,
56/7 = 56 × 3/7 × 3 = 168/21 - Subtract the two like fractions:
40/21 - 168/21 = 40 - 168/21 = -128/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 80/21-56/7 40/42-56/7 40/21-56/14 40/63-56/7 40/21-56/21 40/21-56/35 40/21-56/49