Answers

Add 84/42 and 21/12

1^st number: 2 0/42, 2^nd number: 1 9/12

84/42 + 21/12 is 15/4.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 12 is 84
   
   Next, find the equivalent fraction of both fractional numbers with denominator 84
2. For the 1st fraction, since 42 × 2 = 84,
   84/42 = 84 × 2/42 × 2 = 168/84
3. Likewise, for the 2nd fraction, since 12 × 7 = 84,
   21/12 = 21 × 7/12 × 7 = 147/84
4. Add the two like fractions:
   168/84 + 147/84 = 168 + 147/84 = 315/84
5. 315/84 simplified gives 15/4
6. So, 84/42 + 21/12 = 15/4
   In mixed form: 33/4

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