Subtract 28/21 from 8/30
1st number: 8/30, 2nd number: 1 7/21
8/30 - 28/21 is -16/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
8/30 = 8 × 7/30 × 7 = 56/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
28/21 = 28 × 10/21 × 10 = 280/210 - Subtract the two like fractions:
56/210 - 280/210 = 56 - 280/210 = -224/210 - After reducing the fraction, the answer is -16/15
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 16/30-28/21 8/30-56/21 8/60-28/21 8/30-28/42 24/30-28/21 8/30-84/21 8/90-28/21 8/30-28/63 40/30-28/21 56/30-28/21