Subtract 28/56 from 21/3, Solve 7 0/3

Subtract 28/56 from 21/3

1^st number: 7 0/3, 2^nd number: 28/56

21/3 - 28/56 is 13/2.

Find the least common denominator or LCM of the two denominators:
LCM of 3 and 56 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 3 × 56 = 168,
21/3 = 21 × 56/3 × 56 = 1176/168
Likewise, for the 2nd fraction, since 56 × 3 = 168,
28/56 = 28 × 3/56 × 3 = 84/168
Subtract the two like fractions:
1176/168 - 84/168 = 1176 - 84/168 = 1092/168
After reducing the fraction, the answer is 13/2
In mixed form: 61/2

MathStep (Works offline)

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