Answers

Add 28/81 and 12/21

28/81 + 12/21 is 520/567.

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,
   28/81 = 28 × 7/81 × 7 = 196/567
3. Likewise, for the 2nd fraction, since 21 × 27 = 567,
   12/21 = 12 × 27/21 × 27 = 324/567
4. Add the two like fractions:
   196/567 + 324/567 = 196 + 324/567 = 520/567
5. So, 28/81 + 12/21 = 520/567

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