Answers

Add 54/42 and 70/80

1^st number: 1 12/42, 2^nd number: 70/80

54/42 + 70/80 is 121/56.

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,
   54/42 = 54 × 40/42 × 40 = 2160/1680
3. Likewise, for the 2nd fraction, since 80 × 21 = 1680,
   70/80 = 70 × 21/80 × 21 = 1470/1680
4. Add the two like fractions:
   2160/1680 + 1470/1680 = 2160 + 1470/1680 = 3630/1680
5. 3630/1680 simplified gives 121/56
6. So, 54/42 + 70/80 = 121/56
   In mixed form: 29/56

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