Answers

Add 42/21 and 90/60

1^st number: 2 0/21, 2^nd number: 1 30/60

42/21 + 90/60 is 7/2.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 60 is 420
   
   Next, find the equivalent fraction of both fractional numbers with denominator 420
2. For the 1st fraction, since 21 × 20 = 420,
   42/21 = 42 × 20/21 × 20 = 840/420
3. Likewise, for the 2nd fraction, since 60 × 7 = 420,
   90/60 = 90 × 7/60 × 7 = 630/420
4. Add the two like fractions:
   840/420 + 630/420 = 840 + 630/420 = 1470/420
5. 1470/420 simplified gives 7/2
6. So, 42/21 + 90/60 = 7/2
   In mixed form: 31/2

MathStep (Works offline)

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

Related: ⁸⁴/₂₁+⁹⁰/₆₀ ⁴²/₆₃+⁹⁰/₆₀

Add Fractions Calculator