Answers

Add 42/21 and 45/18

1^st number: 2 0/21, 2^nd number: 2 9/18

42/21 + 45/18 is 9/2.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 18 is 126
   
   Next, find the equivalent fraction of both fractional numbers with denominator 126
2. For the 1st fraction, since 21 × 6 = 126,
   42/21 = 42 × 6/21 × 6 = 252/126
3. Likewise, for the 2nd fraction, since 18 × 7 = 126,
   45/18 = 45 × 7/18 × 7 = 315/126
4. Add the two like fractions:
   252/126 + 315/126 = 252 + 315/126 = 567/126
5. 567/126 simplified gives 9/2
6. So, 42/21 + 45/18 = 9/2
   In mixed form: 41/2

MathStep (Works offline)

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

Related: ⁸⁴/₂₁+⁴⁵/₁₈ ⁴²/₂₁+⁹⁰/₁₈ ⁴²/₂₁+⁴⁵/₃₆ ⁴²/₆₃+⁴⁵/₁₈ ⁴²/₂₁+⁴⁵/₅₄ ⁴²/₂₁+⁴⁵/₉₀

Add Fractions Calculator