Answers

Add 28/72 and 18/81

28/72 + 18/81 is 11/18.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 72 and 81 is 648
   
   Next, find the equivalent fraction of both fractional numbers with denominator 648
2. For the 1st fraction, since 72 × 9 = 648,
   28/72 = 28 × 9/72 × 9 = 252/648
3. Likewise, for the 2nd fraction, since 81 × 8 = 648,
   18/81 = 18 × 8/81 × 8 = 144/648
4. Add the two like fractions:
   252/648 + 144/648 = 252 + 144/648 = 396/648
5. 396/648 simplified gives 11/18
6. So, 28/72 + 18/81 = 11/18

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