Answers

Add 40/81 and 72/20

1^st number: 40/81, 2^nd number: 3 12/20

40/81 + 72/20 is 1658/405.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 81 and 20 is 1620
   
   Next, find the equivalent fraction of both fractional numbers with denominator 1620
2. For the 1st fraction, since 81 × 20 = 1620,
   40/81 = 40 × 20/81 × 20 = 800/1620
3. Likewise, for the 2nd fraction, since 20 × 81 = 1620,
   72/20 = 72 × 81/20 × 81 = 5832/1620
4. Add the two like fractions:
   800/1620 + 5832/1620 = 800 + 5832/1620 = 6632/1620
5. 6632/1620 simplified gives 1658/405
6. So, 40/81 + 72/20 = 1658/405
   In mixed form: 438/405

MathStep (Works offline)

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

Related: ⁸⁰/₈₁+⁷²/₂₀ ⁴⁰/₈₁+⁷²/₄₀ ⁴⁰/₈₁+⁷²/₆₀

Add Fractions Calculator