Answers

Add 12/84 and 28/21

1^st number: 12/84, 2^nd number: 1 7/21

12/84 + 28/21 is 31/21.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 84 and 21 is 84
   
   Next, find the equivalent fraction of both fractional numbers with denominator 84
2. For the 1st fraction, since 84 × 1 = 84,
   12/84 = 12 × 1/84 × 1 = 12/84
3. Likewise, for the 2nd fraction, since 21 × 4 = 84,
   28/21 = 28 × 4/21 × 4 = 112/84
4. Add the two like fractions:
   12/84 + 112/84 = 12 + 112/84 = 124/84
5. 124/84 simplified gives 31/21
6. So, 12/84 + 28/21 = 31/21
   In mixed form: 110/21

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