Subtract 40/49 from 40/72, Solve 40/72

Subtract 40/49 from 40/72

40/72 - 40/49 is -115/441.

Find the least common denominator or LCM of the two denominators:
LCM of 72 and 49 is 3528

Next, find the equivalent fraction of both fractional numbers with denominator 3528
For the 1st fraction, since 72 × 49 = 3528,
40/72 = 40 × 49/72 × 49 = 1960/3528
Likewise, for the 2nd fraction, since 49 × 72 = 3528,
40/49 = 40 × 72/49 × 72 = 2880/3528
Subtract the two like fractions:
1960/3528 - 2880/3528 = 1960 - 2880/3528 = -920/3528
After reducing the fraction, the answer is -115/441

MathStep (Works offline)

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