Subtract 3/42 from 70/20, Solve 3 10/20

Subtract 3/42 from 70/20

1^st number: 3 10/20, 2^nd number: 3/42

70/20 - 3/42 is 24/7.

Find the least common denominator or LCM of the two denominators:
LCM of 20 and 42 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 20 × 21 = 420,
70/20 = 70 × 21/20 × 21 = 1470/420
Likewise, for the 2nd fraction, since 42 × 10 = 420,
3/42 = 3 × 10/42 × 10 = 30/420
Subtract the two like fractions:
1470/420 - 30/420 = 1470 - 30/420 = 1440/420
After reducing the fraction, the answer is 24/7
In mixed form: 33/7

MathStep (Works offline)

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