Subtract 6/10 from 42/21, Solve 2 0/21

Subtract 6/10 from 42/21

1^st number: 2 0/21, 2^nd number: 6/10

42/21 - 6/10 is 7/5.

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,
42/21 = 42 × 10/21 × 10 = 420/210
Likewise, for the 2nd fraction, since 10 × 21 = 210,
6/10 = 6 × 21/10 × 21 = 126/210
Subtract the two like fractions:
420/210 - 126/210 = 420 - 126/210 = 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