Answers

Add 80/21 and 35/45

1^st number: 3 17/21, 2^nd number: 35/45

80/21 + 35/45 is 289/63.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 45 is 315
   
   Next, find the equivalent fraction of both fractional numbers with denominator 315
2. For the 1st fraction, since 21 × 15 = 315,
   80/21 = 80 × 15/21 × 15 = 1200/315
3. Likewise, for the 2nd fraction, since 45 × 7 = 315,
   35/45 = 35 × 7/45 × 7 = 245/315
4. Add the two like fractions:
   1200/315 + 245/315 = 1200 + 245/315 = 1445/315
5. 1445/315 simplified gives 289/63
6. So, 80/21 + 35/45 = 289/63
   In mixed form: 437/63

MathStep (Works offline)

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

Related: ⁸⁰/₂₁+⁷⁰/₄₅ ⁸⁰/₄₂+³⁵/₄₅ ⁸⁰/₂₁+³⁵/₉₀ ⁸⁰/₆₃+³⁵/₄₅

Add Fractions Calculator