Answers

Add 15/21 and 84/45

1^st number: 15/21, 2^nd number: 1 39/45

15/21 + 84/45 is 271/105.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 45 is 315
   
   Next, find the equivalent fraction of both fractional numbers with denominator 315
2. For the 1st fraction, since 21 × 15 = 315,
   15/21 = 15 × 15/21 × 15 = 225/315
3. Likewise, for the 2nd fraction, since 45 × 7 = 315,
   84/45 = 84 × 7/45 × 7 = 588/315
4. Add the two like fractions:
   225/315 + 588/315 = 225 + 588/315 = 813/315
5. 813/315 simplified gives 271/105
6. So, 15/21 + 84/45 = 271/105
   In mixed form: 261/105

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