Answers

Add 21/12 and 18/63

1^st number: 1 9/12, 2^nd number: 18/63

21/12 + 18/63 is 57/28.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 12 and 63 is 252
   
   Next, find the equivalent fraction of both fractional numbers with denominator 252
2. For the 1st fraction, since 12 × 21 = 252,
   21/12 = 21 × 21/12 × 21 = 441/252
3. Likewise, for the 2nd fraction, since 63 × 4 = 252,
   18/63 = 18 × 4/63 × 4 = 72/252
4. Add the two like fractions:
   441/252 + 72/252 = 441 + 72/252 = 513/252
5. 513/252 simplified gives 57/28
6. So, 21/12 + 18/63 = 57/28
   In mixed form: 21/28

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