Subtract 21/18 from 21/25
1st number: 21/25, 2nd number: 1 3/18
21/25 - 21/18 is -49/150.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 25 and 18 is 450
Next, find the equivalent fraction of both fractional numbers with denominator 450 - For the 1st fraction, since 25 × 18 = 450,
21/25 = 21 × 18/25 × 18 = 378/450 - Likewise, for the 2nd fraction, since 18 × 25 = 450,
21/18 = 21 × 25/18 × 25 = 525/450 - Subtract the two like fractions:
378/450 - 525/450 = 378 - 525/450 = -147/450 - After reducing the fraction, the answer is -49/150
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/25-21/18 21/25-42/18 21/50-21/18 21/25-21/36 63/25-21/18 21/25-63/18 21/75-21/18 21/25-21/54 21/25-21/90