Answers

Add 21/98 and 28/81

21/98 + 28/81 is 635/1134.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 98 and 81 is 7938
   
   Next, find the equivalent fraction of both fractional numbers with denominator 7938
2. For the 1st fraction, since 98 × 81 = 7938,
   21/98 = 21 × 81/98 × 81 = 1701/7938
3. Likewise, for the 2nd fraction, since 81 × 98 = 7938,
   28/81 = 28 × 98/81 × 98 = 2744/7938
4. Add the two like fractions:
   1701/7938 + 2744/7938 = 1701 + 2744/7938 = 4445/7938
5. 4445/7938 simplified gives 635/1134
6. So, 21/98 + 28/81 = 635/1134

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