Answers

Add 15/21 and 70/45

1^st number: 15/21, 2^nd number: 1 25/45

15/21 + 70/45 is 143/63.

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,
   70/45 = 70 × 7/45 × 7 = 490/315
4. Add the two like fractions:
   225/315 + 490/315 = 225 + 490/315 = 715/315
5. 715/315 simplified gives 143/63
6. So, 15/21 + 70/45 = 143/63
   In mixed form: 217/63

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