Subtract 63/80 from 27/21, Solve 1 6/21

Subtract 63/80 from 27/21

1^st number: 1 6/21, 2^nd number: 63/80

27/21 - 63/80 is 279/560.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 80 is 1680

Next, find the equivalent fraction of both fractional numbers with denominator 1680
For the 1st fraction, since 21 × 80 = 1680,
27/21 = 27 × 80/21 × 80 = 2160/1680
Likewise, for the 2nd fraction, since 80 × 21 = 1680,
63/80 = 63 × 21/80 × 21 = 1323/1680
Subtract the two like fractions:
2160/1680 - 1323/1680 = 2160 - 1323/1680 = 837/1680
After reducing the fraction, the answer is 279/560

MathStep (Works offline)

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