Answers

Subtract 25/9 from 21/80

1^st number: 21/80, 2^nd number: 2 7/9

21/80 - 25/9 is -1811/720.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 80 and 9 is 720
   
   Next, find the equivalent fraction of both fractional numbers with denominator 720
2. For the 1st fraction, since 80 × 9 = 720,
   21/80 = 21 × 9/80 × 9 = 189/720
3. Likewise, for the 2nd fraction, since 9 × 80 = 720,
   25/9 = 25 × 80/9 × 80 = 2000/720
4. Subtract the two like fractions:
   189/720 - 2000/720 = 189 - 2000/720 = -1811/720

MathStep (Works offline)

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

Related: ⁴²/₈₀-²⁵/₉ ²¹/₈₀-⁵⁰/₉ ²¹/₈₀-²⁵/₁₈ ⁶³/₈₀-²⁵/₉ ²¹/₈₀-⁷⁵/₉ ²¹/₈₀-²⁵/₂₇ ²¹/₈₀-²⁵/₄₅ ²¹/₈₀-²⁵/₆₃

Subtract Fractions Calculator