Answers

Add 20/63 and 21/81

20/63 + 21/81 is 109/189.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 63 and 81 is 567
   
   Next, find the equivalent fraction of both fractional numbers with denominator 567
2. For the 1st fraction, since 63 × 9 = 567,
   20/63 = 20 × 9/63 × 9 = 180/567
3. Likewise, for the 2nd fraction, since 81 × 7 = 567,
   21/81 = 21 × 7/81 × 7 = 147/567
4. Add the two like fractions:
   180/567 + 147/567 = 180 + 147/567 = 327/567
5. 327/567 simplified gives 109/189
6. So, 20/63 + 21/81 = 109/189

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