Answers

Add 81/21 and 54/18

1^st number: 3 18/21, 2^nd number: 3 0/18

81/21 + 54/18 is 48/7.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 18 is 126
   
   Next, find the equivalent fraction of both fractional numbers with denominator 126
2. For the 1st fraction, since 21 × 6 = 126,
   81/21 = 81 × 6/21 × 6 = 486/126
3. Likewise, for the 2nd fraction, since 18 × 7 = 126,
   54/18 = 54 × 7/18 × 7 = 378/126
4. Add the two like fractions:
   486/126 + 378/126 = 486 + 378/126 = 864/126
5. 864/126 simplified gives 48/7
6. So, 81/21 + 54/18 = 48/7
   In mixed form: 66/7

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