Subtract 42/8 from 21/49
1st number: 21/49, 2nd number: 5 2/8
21/49 - 42/8 is -135/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 49 and 8 is 392
Next, find the equivalent fraction of both fractional numbers with denominator 392 - For the 1st fraction, since 49 × 8 = 392,
21/49 = 21 × 8/49 × 8 = 168/392 - Likewise, for the 2nd fraction, since 8 × 49 = 392,
42/8 = 42 × 49/8 × 49 = 2058/392 - Subtract the two like fractions:
168/392 - 2058/392 = 168 - 2058/392 = -1890/392 - After reducing the fraction, the answer is -135/28
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/49-42/8 21/49-84/8 21/98-42/8 21/49-42/16 63/49-42/8 21/49-42/24 21/49-42/40 21/49-42/56