Subtract 45/10 from 4/21, Solve 4/21

Subtract 45/10 from 4/21

1^st number: 4/21, 2^nd number: 4 5/10

4/21 - 45/10 is -181/42.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 10 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 21 × 10 = 210,
4/21 = 4 × 10/21 × 10 = 40/210
Likewise, for the 2nd fraction, since 10 × 21 = 210,
45/10 = 45 × 21/10 × 21 = 945/210
Subtract the two like fractions:
40/210 - 945/210 = 40 - 945/210 = -905/210
After reducing the fraction, the answer is -181/42

MathStep (Works offline)

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