Answers

Add 12/21 and 27/81

12/21 + 27/81 is 19/21.

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,
   12/21 = 12 × 27/21 × 27 = 324/567
3. Likewise, for the 2nd fraction, since 81 × 7 = 567,
   27/81 = 27 × 7/81 × 7 = 189/567
4. Add the two like fractions:
   324/567 + 189/567 = 324 + 189/567 = 513/567
5. 513/567 simplified gives 19/21
6. So, 12/21 + 27/81 = 19/21

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