Subtract 70/54 from 28/70, Solve 28/70

Subtract 70/54 from 28/70

1^st number: 28/70, 2^nd number: 1 16/54

28/70 - 70/54 is -121/135.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 54 is 1890

Next, find the equivalent fraction of both fractional numbers with denominator 1890
For the 1st fraction, since 70 × 27 = 1890,
28/70 = 28 × 27/70 × 27 = 756/1890
Likewise, for the 2nd fraction, since 54 × 35 = 1890,
70/54 = 70 × 35/54 × 35 = 2450/1890
Subtract the two like fractions:
756/1890 - 2450/1890 = 756 - 2450/1890 = -1694/1890
After reducing the fraction, the answer is -121/135

MathStep (Works offline)

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