Answers

Subtract 48/42 from 15/40

1^st number: 15/40, 2^nd number: 1 6/42

15/40 - 48/42 is -43/56.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 40 and 42 is 840
   
   Next, find the equivalent fraction of both fractional numbers with denominator 840
2. For the 1st fraction, since 40 × 21 = 840,
   15/40 = 15 × 21/40 × 21 = 315/840
3. Likewise, for the 2nd fraction, since 42 × 20 = 840,
   48/42 = 48 × 20/42 × 20 = 960/840
4. Subtract the two like fractions:
   315/840 - 960/840 = 315 - 960/840 = -645/840
5. After reducing the fraction, the answer is -43/56

MathStep (Works offline)

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

Related: ³⁰/₄₀-⁴⁸/₄₂ ¹⁵/₄₀-⁹⁶/₄₂ ¹⁵/₈₀-⁴⁸/₄₂ ¹⁵/₄₀-⁴⁸/₈₄ ⁴⁵/₄₀-⁴⁸/₄₂ ⁷⁵/₄₀-⁴⁸/₄₂

Subtract Fractions Calculator