Subtract 25/21 from 21/45
1st number: 21/45, 2nd number: 1 4/21
21/45 - 25/21 is -76/105.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 21 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 45 × 7 = 315,
21/45 = 21 × 7/45 × 7 = 147/315 - Likewise, for the 2nd fraction, since 21 × 15 = 315,
25/21 = 25 × 15/21 × 15 = 375/315 - Subtract the two like fractions:
147/315 - 375/315 = 147 - 375/315 = -228/315 - After reducing the fraction, the answer is -76/105
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/45-25/21 21/45-50/21 21/90-25/21 21/45-25/42 63/45-25/21 21/45-75/21 21/45-25/63