Answers

Add 81/21 and 81/12

1^st number: 3 18/21, 2^nd number: 6 9/12

81/21 + 81/12 is 297/28.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 12 is 84
   
   Next, find the equivalent fraction of both fractional numbers with denominator 84
2. For the 1st fraction, since 21 × 4 = 84,
   81/21 = 81 × 4/21 × 4 = 324/84
3. Likewise, for the 2nd fraction, since 12 × 7 = 84,
   81/12 = 81 × 7/12 × 7 = 567/84
4. Add the two like fractions:
   324/84 + 567/84 = 324 + 567/84 = 891/84
5. 891/84 simplified gives 297/28
6. So, 81/21 + 81/12 = 297/28
   In mixed form: 1017/28

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