Subtract 21/8 from 70/49, Solve 1 21/49

Subtract 21/8 from 70/49

1^st number: 1 21/49, 2^nd number: 2 5/8

70/49 - 21/8 is -67/56.

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,
70/49 = 70 × 8/49 × 8 = 560/392
Likewise, for the 2nd fraction, since 8 × 49 = 392,
21/8 = 21 × 49/8 × 49 = 1029/392
Subtract the two like fractions:
560/392 - 1029/392 = 560 - 1029/392 = -469/392
After reducing the fraction, the answer is -67/56

MathStep (Works offline)

Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad