Subtract 21/7 from 49/20
1st number: 2 9/20, 2nd number: 3 0/7
49/20 - 21/7 is -11/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 7 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 20 × 7 = 140,
49/20 = 49 × 7/20 × 7 = 343/140 - Likewise, for the 2nd fraction, since 7 × 20 = 140,
21/7 = 21 × 20/7 × 20 = 420/140 - Subtract the two like fractions:
343/140 - 420/140 = 343 - 420/140 = -77/140 - After reducing the fraction, the answer is -11/20
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 98/20-21/7 49/20-42/7 49/40-21/7 49/20-21/14 49/20-63/7 49/60-21/7 49/20-21/35 49/20-21/49