Subtract 2/40 from 45/42, Solve 1 3/42

Subtract 2/40 from 45/42

1^st number: 1 3/42, 2^nd number: 2/40

45/42 - 2/40 is 143/140.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 40 is 840

Next, find the equivalent fraction of both fractional numbers with denominator 840
For the 1st fraction, since 42 × 20 = 840,
45/42 = 45 × 20/42 × 20 = 900/840
Likewise, for the 2nd fraction, since 40 × 21 = 840,
2/40 = 2 × 21/40 × 21 = 42/840
Subtract the two like fractions:
900/840 - 42/840 = 900 - 42/840 = 858/840
After reducing the fraction, the answer is 143/140
In mixed form: 13/140

MathStep (Works offline)

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