Answers

Subtract 81/80 from 50/72

1^st number: 50/72, 2^nd number: 1 1/80

50/72 - 81/80 is -229/720.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 72 and 80 is 720
   
   Next, find the equivalent fraction of both fractional numbers with denominator 720
2. For the 1st fraction, since 72 × 10 = 720,
   50/72 = 50 × 10/72 × 10 = 500/720
3. Likewise, for the 2nd fraction, since 80 × 9 = 720,
   81/80 = 81 × 9/80 × 9 = 729/720
4. Subtract the two like fractions:
   500/720 - 729/720 = 500 - 729/720 = -229/720

MathStep (Works offline)

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

Related:

Subtract Fractions Calculator