Answers

Add 80/21 and 84/12

1^st number: 3 17/21, 2^nd number: 7 0/12

80/21 + 84/12 is 227/21.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 12 is 84
   
   Next, find the equivalent fraction of both fractional numbers with denominator 84
2. For the 1st fraction, since 21 × 4 = 84,
   80/21 = 80 × 4/21 × 4 = 320/84
3. Likewise, for the 2nd fraction, since 12 × 7 = 84,
   84/12 = 84 × 7/12 × 7 = 588/84
4. Add the two like fractions:
   320/84 + 588/84 = 320 + 588/84 = 908/84
5. 908/84 simplified gives 227/21
6. So, 80/21 + 84/12 = 227/21
   In mixed form: 1017/21

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