Subtract 28/21 from 8/5
1st number: 1 3/5, 2nd number: 1 7/21
8/5 - 28/21 is 4/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 5 × 21 = 105,
8/5 = 8 × 21/5 × 21 = 168/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
28/21 = 28 × 5/21 × 5 = 140/105 - Subtract the two like fractions:
168/105 - 140/105 = 168 - 140/105 = 28/105 - After reducing the fraction, the answer is 4/15
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 16/5-28/21 8/5-56/21 8/10-28/21 8/5-28/42 24/5-28/21 8/5-84/21 8/15-28/21 8/5-28/63 40/5-28/21 8/25-28/21 56/5-28/21 8/35-28/21