Answers

Add 45/12 and 8/21

1^st number: 3 9/12, 2^nd number: 8/21

45/12 + 8/21 is 347/84.

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,
   45/12 = 45 × 7/12 × 7 = 315/84
3. Likewise, for the 2nd fraction, since 21 × 4 = 84,
   8/21 = 8 × 4/21 × 4 = 32/84
4. Add the two like fractions:
   315/84 + 32/84 = 315 + 32/84 = 347/84
5. So, 45/12 + 8/21 = 347/84
   In mixed form: 411/84

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