Answers

Add 12/84 and 80/81

12/84 + 80/81 is 641/567.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 84 and 81 is 2268
   
   Next, find the equivalent fraction of both fractional numbers with denominator 2268
2. For the 1st fraction, since 84 × 27 = 2268,
   12/84 = 12 × 27/84 × 27 = 324/2268
3. Likewise, for the 2nd fraction, since 81 × 28 = 2268,
   80/81 = 80 × 28/81 × 28 = 2240/2268
4. Add the two like fractions:
   324/2268 + 2240/2268 = 324 + 2240/2268 = 2564/2268
5. 2564/2268 simplified gives 641/567
6. So, 12/84 + 80/81 = 641/567
   In mixed form: 174/567

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