Subtract 2/70 from 30/21, Solve 1 9/21

Subtract 2/70 from 30/21

1^st number: 1 9/21, 2^nd number: 2/70

30/21 - 2/70 is 7/5.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 70 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 21 × 10 = 210,
30/21 = 30 × 10/21 × 10 = 300/210
Likewise, for the 2nd fraction, since 70 × 3 = 210,
2/70 = 2 × 3/70 × 3 = 6/210
Subtract the two like fractions:
300/210 - 6/210 = 300 - 6/210 = 294/210
After reducing the fraction, the answer is 7/5
In mixed form: 12/5

MathStep (Works offline)

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