Subtract 10/45 from 40/21, Solve 1 19/21

Subtract 10/45 from 40/21

1^st number: 1 19/21, 2^nd number: 10/45

40/21 - 10/45 is 106/63.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 45 is 315

Next, find the equivalent fraction of both fractional numbers with denominator 315
For the 1st fraction, since 21 × 15 = 315,
40/21 = 40 × 15/21 × 15 = 600/315
Likewise, for the 2nd fraction, since 45 × 7 = 315,
10/45 = 10 × 7/45 × 7 = 70/315
Subtract the two like fractions:
600/315 - 70/315 = 600 - 70/315 = 530/315
After reducing the fraction, the answer is 106/63
In mixed form: 143/63

MathStep (Works offline)

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