Answers

Add 21/30 and 90/81

1^st number: 21/30, 2^nd number: 1 9/81

21/30 + 90/81 is 163/90.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 30 and 81 is 810
   
   Next, find the equivalent fraction of both fractional numbers with denominator 810
2. For the 1st fraction, since 30 × 27 = 810,
   21/30 = 21 × 27/30 × 27 = 567/810
3. Likewise, for the 2nd fraction, since 81 × 10 = 810,
   90/81 = 90 × 10/81 × 10 = 900/810
4. Add the two like fractions:
   567/810 + 900/810 = 567 + 900/810 = 1467/810
5. 1467/810 simplified gives 163/90
6. So, 21/30 + 90/81 = 163/90
   In mixed form: 173/90

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