Answers

Add 81/18 and 70/21

1^st number: 4 9/18, 2^nd number: 3 7/21

81/18 + 70/21 is 47/6.

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,
   81/18 = 81 × 7/18 × 7 = 567/126
3. Likewise, for the 2nd fraction, since 21 × 6 = 126,
   70/21 = 70 × 6/21 × 6 = 420/126
4. Add the two like fractions:
   567/126 + 420/126 = 567 + 420/126 = 987/126
5. 987/126 simplified gives 47/6
6. So, 81/18 + 70/21 = 47/6
   In mixed form: 75/6

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