Answers

Add 21/60 and 90/81

1^st number: 21/60, 2^nd number: 1 9/81

21/60 + 90/81 is 263/180.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 60 and 81 is 1620
   
   Next, find the equivalent fraction of both fractional numbers with denominator 1620
2. For the 1st fraction, since 60 × 27 = 1620,
   21/60 = 21 × 27/60 × 27 = 567/1620
3. Likewise, for the 2nd fraction, since 81 × 20 = 1620,
   90/81 = 90 × 20/81 × 20 = 1800/1620
4. Add the two like fractions:
   567/1620 + 1800/1620 = 567 + 1800/1620 = 2367/1620
5. 2367/1620 simplified gives 263/180
6. So, 21/60 + 90/81 = 263/180
   In mixed form: 183/180

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