Answers

Add 20/72 and 5/81

20/72 + 5/81 is 55/162.

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,
   20/72 = 20 × 9/72 × 9 = 180/648
3. Likewise, for the 2nd fraction, since 81 × 8 = 648,
   5/81 = 5 × 8/81 × 8 = 40/648
4. Add the two like fractions:
   180/648 + 40/648 = 180 + 40/648 = 220/648
5. 220/648 simplified gives 55/162
6. So, 20/72 + 5/81 = 55/162

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