Answers

Add 28/90 and 15/81

28/90 + 15/81 is 67/135.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 90 and 81 is 810
   
   Next, find the equivalent fraction of both fractional numbers with denominator 810
2. For the 1st fraction, since 90 × 9 = 810,
   28/90 = 28 × 9/90 × 9 = 252/810
3. Likewise, for the 2nd fraction, since 81 × 10 = 810,
   15/81 = 15 × 10/81 × 10 = 150/810
4. Add the two like fractions:
   252/810 + 150/810 = 252 + 150/810 = 402/810
5. 402/810 simplified gives 67/135
6. So, 28/90 + 15/81 = 67/135

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