Answers

Add 70/21 and 20/81

1^st number: 3 7/21, 2^nd number: 20/81

70/21 + 20/81 is 290/81.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 81 is 567
   
   Next, find the equivalent fraction of both fractional numbers with denominator 567
2. For the 1st fraction, since 21 × 27 = 567,
   70/21 = 70 × 27/21 × 27 = 1890/567
3. Likewise, for the 2nd fraction, since 81 × 7 = 567,
   20/81 = 20 × 7/81 × 7 = 140/567
4. Add the two like fractions:
   1890/567 + 140/567 = 1890 + 140/567 = 2030/567
5. 2030/567 simplified gives 290/81
6. So, 70/21 + 20/81 = 290/81
   In mixed form: 347/81

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