Answers

Add 21/10 and 18/81

1^st number: 2 1/10, 2^nd number: 18/81

21/10 + 18/81 is 209/90.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 10 and 81 is 810
   
   Next, find the equivalent fraction of both fractional numbers with denominator 810
2. For the 1st fraction, since 10 × 81 = 810,
   21/10 = 21 × 81/10 × 81 = 1701/810
3. Likewise, for the 2nd fraction, since 81 × 10 = 810,
   18/81 = 18 × 10/81 × 10 = 180/810
4. Add the two like fractions:
   1701/810 + 180/810 = 1701 + 180/810 = 1881/810
5. 1881/810 simplified gives 209/90
6. So, 21/10 + 18/81 = 209/90
   In mixed form: 229/90

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