Subtract 21/15 from 40/28
1st number: 1 12/28, 2nd number: 1 6/15
40/28 - 21/15 is 1/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 15 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 28 × 15 = 420,
40/28 = 40 × 15/28 × 15 = 600/420 - Likewise, for the 2nd fraction, since 15 × 28 = 420,
21/15 = 21 × 28/15 × 28 = 588/420 - Subtract the two like fractions:
600/420 - 588/420 = 600 - 588/420 = 12/420 - After reducing the fraction, the answer is 1/35
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 80/28-21/15 40/28-42/15 40/56-21/15 40/28-21/30 40/28-63/15 40/84-21/15 40/28-21/45 40/28-21/75