Answers

Add 84/12 and 42/21

1^st number: 7 0/12, 2^nd number: 2 0/21

84/12 + 42/21 is 9/1.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 12 and 21 is 84
   
   Next, find the equivalent fraction of both fractional numbers with denominator 84
2. For the 1st fraction, since 12 × 7 = 84,
   84/12 = 84 × 7/12 × 7 = 588/84
3. Likewise, for the 2nd fraction, since 21 × 4 = 84,
   42/21 = 42 × 4/21 × 4 = 168/84
4. Add the two like fractions:
   588/84 + 168/84 = 588 + 168/84 = 756/84
5. 756/84 simplified gives 9/1
6. So, 84/12 + 42/21 = 9/1

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