Answers

Add 70/21 and 45/12

1^st number: 3 7/21, 2^nd number: 3 9/12

70/21 + 45/12 is 85/12.

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,
   70/21 = 70 × 4/21 × 4 = 280/84
3. Likewise, for the 2nd fraction, since 12 × 7 = 84,
   45/12 = 45 × 7/12 × 7 = 315/84
4. Add the two like fractions:
   280/84 + 315/84 = 280 + 315/84 = 595/84
5. 595/84 simplified gives 85/12
6. So, 70/21 + 45/12 = 85/12
   In mixed form: 71/12

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