Subtract 56/20 from 1/21, Solve 1/21

Subtract 56/20 from 1/21

1^st number: 1/21, 2^nd number: 2 16/20

1/21 - 56/20 is -289/105.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 20 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 21 × 20 = 420,
1/21 = 1 × 20/21 × 20 = 20/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
56/20 = 56 × 21/20 × 21 = 1176/420
Subtract the two like fractions:
20/420 - 1176/420 = 20 - 1176/420 = -1156/420
After reducing the fraction, the answer is -289/105

MathStep (Works offline)

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