Answers

Add 81/21 and 54/12

1^st number: 3 18/21, 2^nd number: 4 6/12

81/21 + 54/12 is 117/14.

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,
   54/12 = 54 × 7/12 × 7 = 378/84
4. Add the two like fractions:
   324/84 + 378/84 = 324 + 378/84 = 702/84
5. 702/84 simplified gives 117/14
6. So, 81/21 + 54/12 = 117/14
   In mixed form: 85/14

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