Subtract 15/64 from 49/21, Solve 2 7/21

Subtract 15/64 from 49/21

1^st number: 2 7/21, 2^nd number: 15/64

49/21 - 15/64 is 403/192.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 64 is 1344

Next, find the equivalent fraction of both fractional numbers with denominator 1344
For the 1st fraction, since 21 × 64 = 1344,
49/21 = 49 × 64/21 × 64 = 3136/1344
Likewise, for the 2nd fraction, since 64 × 21 = 1344,
15/64 = 15 × 21/64 × 21 = 315/1344
Subtract the two like fractions:
3136/1344 - 315/1344 = 3136 - 315/1344 = 2821/1344
After reducing the fraction, the answer is 403/192
In mixed form: 219/192

MathStep (Works offline)

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