Answers

Add 81/42 and 70/40

1^st number: 1 39/42, 2^nd number: 1 30/40

81/42 + 70/40 is 103/28.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 40 is 840
   
   Next, find the equivalent fraction of both fractional numbers with denominator 840
2. For the 1st fraction, since 42 × 20 = 840,
   81/42 = 81 × 20/42 × 20 = 1620/840
3. Likewise, for the 2nd fraction, since 40 × 21 = 840,
   70/40 = 70 × 21/40 × 21 = 1470/840
4. Add the two like fractions:
   1620/840 + 1470/840 = 1620 + 1470/840 = 3090/840
5. 3090/840 simplified gives 103/28
6. So, 81/42 + 70/40 = 103/28
   In mixed form: 319/28

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