Subtract 28/35 from 21/30
21/30 - 28/35 is -1/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 35 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
21/30 = 21 × 7/30 × 7 = 147/210 - Likewise, for the 2nd fraction, since 35 × 6 = 210,
28/35 = 28 × 6/35 × 6 = 168/210 - Subtract the two like fractions:
147/210 - 168/210 = 147 - 168/210 = -21/210 - After reducing the fraction, the answer is -1/10
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/30-28/35 21/30-56/35 21/60-28/35 21/30-28/70 63/30-28/35 21/30-84/35 21/90-28/35