Subtract 56/18 from 21/7
1st number: 3 0/7, 2nd number: 3 2/18
21/7 - 56/18 is -1/9.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 7 × 18 = 126,
21/7 = 21 × 18/7 × 18 = 378/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
56/18 = 56 × 7/18 × 7 = 392/126 - Subtract the two like fractions:
378/126 - 392/126 = 378 - 392/126 = -14/126 - After reducing the fraction, the answer is -1/9
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/7-56/18 21/14-56/18 21/7-56/36 63/7-56/18 21/7-56/54 21/35-56/18 21/7-56/90 21/49-56/18