Answers

Add 18/21 and 40/81

18/21 + 40/81 is 766/567.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 81 is 567
   
   Next, find the equivalent fraction of both fractional numbers with denominator 567
2. For the 1st fraction, since 21 × 27 = 567,
   18/21 = 18 × 27/21 × 27 = 486/567
3. Likewise, for the 2nd fraction, since 81 × 7 = 567,
   40/81 = 40 × 7/81 × 7 = 280/567
4. Add the two like fractions:
   486/567 + 280/567 = 486 + 280/567 = 766/567
5. So, 18/21 + 40/81 = 766/567
   In mixed form: 1199/567

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