Subtract 72/7 from 40/21
1st number: 1 19/21, 2nd number: 10 2/7
40/21 - 72/7 is -176/21.
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,
72/7 = 72 × 3/7 × 3 = 216/21 - Subtract the two like fractions:
40/21 - 216/21 = 40 - 216/21 = -176/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 80/21-72/7 40/42-72/7 40/21-72/14 40/63-72/7 40/21-72/21 40/21-72/35 40/21-72/49