Answers

Add 81/42 and 70/80

1^st number: 1 39/42, 2^nd number: 70/80

81/42 + 70/80 is 157/56.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 80 is 1680
   
   Next, find the equivalent fraction of both fractional numbers with denominator 1680
2. For the 1st fraction, since 42 × 40 = 1680,
   81/42 = 81 × 40/42 × 40 = 3240/1680
3. Likewise, for the 2nd fraction, since 80 × 21 = 1680,
   70/80 = 70 × 21/80 × 21 = 1470/1680
4. Add the two like fractions:
   3240/1680 + 1470/1680 = 3240 + 1470/1680 = 4710/1680
5. 4710/1680 simplified gives 157/56
6. So, 81/42 + 70/80 = 157/56
   In mixed form: 245/56

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