Answers

Add 21/42 and 98/81

1^st number: 21/42, 2^nd number: 1 17/81

21/42 + 98/81 is 277/162.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 81 is 1134
   
   Next, find the equivalent fraction of both fractional numbers with denominator 1134
2. For the 1st fraction, since 42 × 27 = 1134,
   21/42 = 21 × 27/42 × 27 = 567/1134
3. Likewise, for the 2nd fraction, since 81 × 14 = 1134,
   98/81 = 98 × 14/81 × 14 = 1372/1134
4. Add the two like fractions:
   567/1134 + 1372/1134 = 567 + 1372/1134 = 1939/1134
5. 1939/1134 simplified gives 277/162
6. So, 21/42 + 98/81 = 277/162
   In mixed form: 1115/162

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