Answers

Add 70/90 and 15/81

70/90 + 15/81 is 26/27.

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,
   70/90 = 70 × 9/90 × 9 = 630/810
3. Likewise, for the 2nd fraction, since 81 × 10 = 810,
   15/81 = 15 × 10/81 × 10 = 150/810
4. Add the two like fractions:
   630/810 + 150/810 = 630 + 150/810 = 780/810
5. 780/810 simplified gives 26/27
6. So, 70/90 + 15/81 = 26/27

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