Answers

Add 72/21 and 84/45

1^st number: 3 9/21, 2^nd number: 1 39/45

72/21 + 84/45 is 556/105.

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,
   72/21 = 72 × 15/21 × 15 = 1080/315
3. Likewise, for the 2nd fraction, since 45 × 7 = 315,
   84/45 = 84 × 7/45 × 7 = 588/315
4. Add the two like fractions:
   1080/315 + 588/315 = 1080 + 588/315 = 1668/315
5. 1668/315 simplified gives 556/105
6. So, 72/21 + 84/45 = 556/105
   In mixed form: 531/105

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