Subtract 21/28 from 2/80, Solve 2/80

Subtract 21/28 from 2/80

2/80 - 21/28 is -29/40.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 28 is 560

Next, find the equivalent fraction of both fractional numbers with denominator 560
For the 1st fraction, since 80 × 7 = 560,
2/80 = 2 × 7/80 × 7 = 14/560
Likewise, for the 2nd fraction, since 28 × 20 = 560,
21/28 = 21 × 20/28 × 20 = 420/560
Subtract the two like fractions:
14/560 - 420/560 = 14 - 420/560 = -406/560
After reducing the fraction, the answer is -29/40

MathStep (Works offline)

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