Answers

Add 70/18 and 81/21

1^st number: 3 16/18, 2^nd number: 3 18/21

70/18 + 81/21 is 488/63.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 18 and 21 is 126
   
   Next, find the equivalent fraction of both fractional numbers with denominator 126
2. For the 1st fraction, since 18 × 7 = 126,
   70/18 = 70 × 7/18 × 7 = 490/126
3. Likewise, for the 2nd fraction, since 21 × 6 = 126,
   81/21 = 81 × 6/21 × 6 = 486/126
4. Add the two like fractions:
   490/126 + 486/126 = 490 + 486/126 = 976/126
5. 976/126 simplified gives 488/63
6. So, 70/18 + 81/21 = 488/63
   In mixed form: 747/63

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