Answers

Add 21/20 and 63/84

1^st number: 1 1/20, 2^nd number: 63/84

21/20 + 63/84 is 9/5.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 20 and 84 is 420
   
   Next, find the equivalent fraction of both fractional numbers with denominator 420
2. For the 1st fraction, since 20 × 21 = 420,
   21/20 = 21 × 21/20 × 21 = 441/420
3. Likewise, for the 2nd fraction, since 84 × 5 = 420,
   63/84 = 63 × 5/84 × 5 = 315/420
4. Add the two like fractions:
   441/420 + 315/420 = 441 + 315/420 = 756/420
5. 756/420 simplified gives 9/5
6. So, 21/20 + 63/84 = 9/5
   In mixed form: 14/5

MathStep (Works offline)

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

Related: ⁴²/₂₀+⁶³/₈₄ ²¹/₄₀+⁶³/₈₄ ⁶³/₂₀+⁶³/₈₄ ²¹/₆₀+⁶³/₈₄

Add Fractions Calculator