Answers

Add 21/84 and 90/63

1^st number: 21/84, 2^nd number: 1 27/63

21/84 + 90/63 is 47/28.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 84 and 63 is 252
   
   Next, find the equivalent fraction of both fractional numbers with denominator 252
2. For the 1st fraction, since 84 × 3 = 252,
   21/84 = 21 × 3/84 × 3 = 63/252
3. Likewise, for the 2nd fraction, since 63 × 4 = 252,
   90/63 = 90 × 4/63 × 4 = 360/252
4. Add the two like fractions:
   63/252 + 360/252 = 63 + 360/252 = 423/252
5. 423/252 simplified gives 47/28
6. So, 21/84 + 90/63 = 47/28
   In mixed form: 119/28

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