Answers

Add 81/21 and 18/63

1^st number: 3 18/21, 2^nd number: 18/63

81/21 + 18/63 is 29/7.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 63 is 63
   
   Next, find the equivalent fraction of both fractional numbers with denominator 63
2. For the 1st fraction, since 21 × 3 = 63,
   81/21 = 81 × 3/21 × 3 = 243/63
3. Likewise, for the 2nd fraction, since 63 × 1 = 63,
   18/63 = 18 × 1/63 × 1 = 18/63
4. Add the two like fractions:
   243/63 + 18/63 = 243 + 18/63 = 261/63
5. 261/63 simplified gives 29/7
6. So, 81/21 + 18/63 = 29/7
   In mixed form: 41/7

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