Subtract 36/7 from 72/80, Solve 72/80

Subtract 36/7 from 72/80

1^st number: 72/80, 2^nd number: 5 1/7

72/80 - 36/7 is -297/70.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 7 is 560

Next, find the equivalent fraction of both fractional numbers with denominator 560
For the 1st fraction, since 80 × 7 = 560,
72/80 = 72 × 7/80 × 7 = 504/560
Likewise, for the 2nd fraction, since 7 × 80 = 560,
36/7 = 36 × 80/7 × 80 = 2880/560
Subtract the two like fractions:
504/560 - 2880/560 = 504 - 2880/560 = -2376/560
After reducing the fraction, the answer is -297/70

MathStep (Works offline)

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