Answers

Add 84/81 and 75/21

1^st number: 1 3/81, 2^nd number: 3 12/21

84/81 + 75/21 is 871/189.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 81 and 21 is 567
   
   Next, find the equivalent fraction of both fractional numbers with denominator 567
2. For the 1st fraction, since 81 × 7 = 567,
   84/81 = 84 × 7/81 × 7 = 588/567
3. Likewise, for the 2nd fraction, since 21 × 27 = 567,
   75/21 = 75 × 27/21 × 27 = 2025/567
4. Add the two like fractions:
   588/567 + 2025/567 = 588 + 2025/567 = 2613/567
5. 2613/567 simplified gives 871/189
6. So, 84/81 + 75/21 = 871/189
   In mixed form: 4115/189

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