Answers

Add 80/12 and 45/21

1^st number: 6 8/12, 2^nd number: 2 3/21

80/12 + 45/21 is 185/21.

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,
   80/12 = 80 × 7/12 × 7 = 560/84
3. Likewise, for the 2nd fraction, since 21 × 4 = 84,
   45/21 = 45 × 4/21 × 4 = 180/84
4. Add the two like fractions:
   560/84 + 180/84 = 560 + 180/84 = 740/84
5. 740/84 simplified gives 185/21
6. So, 80/12 + 45/21 = 185/21
   In mixed form: 817/21

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