Subtract 10/5 from 2/21, Solve 2/21

Subtract 10/5 from 2/21

1^st number: 2/21, 2^nd number: 2 0/5

2/21 - 10/5 is -40/21.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 5 is 105

Next, find the equivalent fraction of both fractional numbers with denominator 105
For the 1st fraction, since 21 × 5 = 105,
2/21 = 2 × 5/21 × 5 = 10/105
Likewise, for the 2nd fraction, since 5 × 21 = 105,
10/5 = 10 × 21/5 × 21 = 210/105
Subtract the two like fractions:
10/105 - 210/105 = 10 - 210/105 = -200/105
After reducing the fraction, the answer is -40/21

MathStep (Works offline)

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