Subtract 15/28 from 6/21
6/21 - 15/28 is -1/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 28 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
6/21 = 6 × 4/21 × 4 = 24/84 - Likewise, for the 2nd fraction, since 28 × 3 = 84,
15/28 = 15 × 3/28 × 3 = 45/84 - Subtract the two like fractions:
24/84 - 45/84 = 24 - 45/84 = -21/84 - After reducing the fraction, the answer is -1/4
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 12/21-15/28 6/21-30/28 6/42-15/28 6/21-15/56 18/21-15/28 6/21-45/28 6/63-15/28 6/21-15/84 30/21-15/28 6/21-75/28 42/21-15/28