Subtract 15/21 from 25/8
1st number: 3 1/8, 2nd number: 15/21
25/8 - 15/21 is 135/56.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 21 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 8 × 21 = 168,
25/8 = 25 × 21/8 × 21 = 525/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
15/21 = 15 × 8/21 × 8 = 120/168 - Subtract the two like fractions:
525/168 - 120/168 = 525 - 120/168 = 405/168 - After reducing the fraction, the answer is 135/56
- In mixed form: 223/56
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 50/8-15/21 25/8-30/21 25/16-15/21 25/8-15/42 75/8-15/21 25/8-45/21 25/24-15/21 25/8-15/63 25/8-75/21 25/40-15/21 25/56-15/21