Answers

Add 18/81 and 21/8

1^st number: 18/81, 2^nd number: 2 5/8

18/81 + 21/8 is 205/72.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 81 and 8 is 648
   
   Next, find the equivalent fraction of both fractional numbers with denominator 648
2. For the 1st fraction, since 81 × 8 = 648,
   18/81 = 18 × 8/81 × 8 = 144/648
3. Likewise, for the 2nd fraction, since 8 × 81 = 648,
   21/8 = 21 × 81/8 × 81 = 1701/648
4. Add the two like fractions:
   144/648 + 1701/648 = 144 + 1701/648 = 1845/648
5. 1845/648 simplified gives 205/72
6. So, 18/81 + 21/8 = 205/72
   In mixed form: 261/72

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