Answers

Subtract 45/54 from 20/72

20/72 - 45/54 is -5/9.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 72 and 54 is 216
   
   Next, find the equivalent fraction of both fractional numbers with denominator 216
2. For the 1st fraction, since 72 × 3 = 216,
   20/72 = 20 × 3/72 × 3 = 60/216
3. Likewise, for the 2nd fraction, since 54 × 4 = 216,
   45/54 = 45 × 4/54 × 4 = 180/216
4. Subtract the two like fractions:
   60/216 - 180/216 = 60 - 180/216 = -120/216
5. After reducing the fraction, the answer is -5/9

MathStep (Works offline)

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

Related: ⁴⁰/₇₂-⁴⁵/₅₄ ²⁰/₇₂-⁹⁰/₅₄ ⁶⁰/₇₂-⁴⁵/₅₄

Subtract Fractions Calculator