Answers

Add 21/15 and 30/81

1^st number: 1 6/15, 2^nd number: 30/81

21/15 + 30/81 is 239/135.

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,
   30/81 = 30 × 5/81 × 5 = 150/405
4. Add the two like fractions:
   567/405 + 150/405 = 567 + 150/405 = 717/405
5. 717/405 simplified gives 239/135
6. So, 21/15 + 30/81 = 239/135
   In mixed form: 1104/135

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