Answers

Subtract 40/21 from 40/18

1^st number: 2 4/18, 2^nd number: 1 19/21

40/18 - 40/21 is 20/63.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 18 and 21 is 126
2. For the 1st fraction, since 18 × 7 = 126,
   40/18 = 40 × 7/18 × 7 = 280/126
3. Likewise, for the 2nd fraction, since 21 × 6 = 126,
   40/21 = 40 × 6/21 × 6 = 240/126
4. Subtract the two fractions:
   280/126 - 240/126 = 280 - 240/126 = 40/126
5. After reducing the fraction, the answer is 20/63

MathStep (Works offline)

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

Related: ⁸⁰/₁₈-⁴⁰/₂₁ ⁴⁰/₁₈-⁸⁰/₂₁ ⁴⁰/₃₆-⁴⁰/₂₁ ⁴⁰/₁₈-⁴⁰/₄₂ ⁴⁰/₅₄-⁴⁰/₂₁ ⁴⁰/₁₈-⁴⁰/₆₃ ⁴⁰/₉₀-⁴⁰/₂₁

Subtract Fractions Calculator