Answers

Add 80/21 and 15/81

1^st number: 3 17/21, 2^nd number: 15/81

80/21 + 15/81 is 755/189.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 81 is 567
   
   Next, find the equivalent fraction of both fractional numbers with denominator 567
2. For the 1st fraction, since 21 × 27 = 567,
   80/21 = 80 × 27/21 × 27 = 2160/567
3. Likewise, for the 2nd fraction, since 81 × 7 = 567,
   15/81 = 15 × 7/81 × 7 = 105/567
4. Add the two like fractions:
   2160/567 + 105/567 = 2160 + 105/567 = 2265/567
5. 2265/567 simplified gives 755/189
6. So, 80/21 + 15/81 = 755/189
   In mixed form: 3188/189

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