Answers

Add 21/15 and 84/81

1^st number: 1 6/15, 2^nd number: 1 3/81

21/15 + 84/81 is 329/135.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 15 and 81 is 405
   
   Next, find the equivalent fraction of both fractional numbers with denominator 405
2. For the 1st fraction, since 15 × 27 = 405,
   21/15 = 21 × 27/15 × 27 = 567/405
3. Likewise, for the 2nd fraction, since 81 × 5 = 405,
   84/81 = 84 × 5/81 × 5 = 420/405
4. Add the two like fractions:
   567/405 + 420/405 = 567 + 420/405 = 987/405
5. 987/405 simplified gives 329/135
6. So, 21/15 + 84/81 = 329/135
   In mixed form: 259/135

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