Answers

Add 90/81 and 21/70

1^st number: 1 9/81, 2^nd number: 21/70

90/81 + 21/70 is 127/90.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 81 and 70 is 5670
   
   Next, find the equivalent fraction of both fractional numbers with denominator 5670
2. For the 1st fraction, since 81 × 70 = 5670,
   90/81 = 90 × 70/81 × 70 = 6300/5670
3. Likewise, for the 2nd fraction, since 70 × 81 = 5670,
   21/70 = 21 × 81/70 × 81 = 1701/5670
4. Add the two like fractions:
   6300/5670 + 1701/5670 = 6300 + 1701/5670 = 8001/5670
5. 8001/5670 simplified gives 127/90
6. So, 90/81 + 21/70 = 127/90
   In mixed form: 137/90

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