Answers

Add 20/81 and 21/63

20/81 + 21/63 is 47/81.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 81 and 63 is 567
   
   Next, find the equivalent fraction of both fractional numbers with denominator 567
2. For the 1st fraction, since 81 × 7 = 567,
   20/81 = 20 × 7/81 × 7 = 140/567
3. Likewise, for the 2nd fraction, since 63 × 9 = 567,
   21/63 = 21 × 9/63 × 9 = 189/567
4. Add the two like fractions:
   140/567 + 189/567 = 140 + 189/567 = 329/567
5. 329/567 simplified gives 47/81
6. So, 20/81 + 21/63 = 47/81

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