Answers

Add 20/70 and 90/72

1^st number: 20/70, 2^nd number: 1 18/72

20/70 + 90/72 is 43/28.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 70 and 72 is 2520
   
   Next, find the equivalent fraction of both fractional numbers with denominator 2520
2. For the 1st fraction, since 70 × 36 = 2520,
   20/70 = 20 × 36/70 × 36 = 720/2520
3. Likewise, for the 2nd fraction, since 72 × 35 = 2520,
   90/72 = 90 × 35/72 × 35 = 3150/2520
4. Add the two like fractions:
   720/2520 + 3150/2520 = 720 + 3150/2520 = 3870/2520
5. 3870/2520 simplified gives 43/28
6. So, 20/70 + 90/72 = 43/28
   In mixed form: 115/28

MathStep (Works offline)

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

Related: ⁴⁰/₇₀+⁹⁰/₇₂ ⁶⁰/₇₀+⁹⁰/₇₂

Add Fractions Calculator