Answers

Add 54/21 and 90/15

1^st number: 2 12/21, 2^nd number: 6 0/15

54/21 + 90/15 is 60/7.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 15 is 105
   
   Next, find the equivalent fraction of both fractional numbers with denominator 105
2. For the 1st fraction, since 21 × 5 = 105,
   54/21 = 54 × 5/21 × 5 = 270/105
3. Likewise, for the 2nd fraction, since 15 × 7 = 105,
   90/15 = 90 × 7/15 × 7 = 630/105
4. Add the two like fractions:
   270/105 + 630/105 = 270 + 630/105 = 900/105
5. 900/105 simplified gives 60/7
6. So, 54/21 + 90/15 = 60/7
   In mixed form: 84/7

MathStep (Works offline)

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

Related: ⁵⁴/₄₂+⁹⁰/₁₅ ⁵⁴/₂₁+⁹⁰/₃₀ ⁵⁴/₆₃+⁹⁰/₁₅ ⁵⁴/₂₁+⁹⁰/₄₅ ⁵⁴/₂₁+⁹⁰/₇₅

Add Fractions Calculator