Answers

Add 70/42 and 45/20

1^st number: 1 28/42, 2^nd number: 2 5/20

70/42 + 45/20 is 47/12.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 20 is 420
   
   Next, find the equivalent fraction of both fractional numbers with denominator 420
2. For the 1st fraction, since 42 × 10 = 420,
   70/42 = 70 × 10/42 × 10 = 700/420
3. Likewise, for the 2nd fraction, since 20 × 21 = 420,
   45/20 = 45 × 21/20 × 21 = 945/420
4. Add the two like fractions:
   700/420 + 945/420 = 700 + 945/420 = 1645/420
5. 1645/420 simplified gives 47/12
6. So, 70/42 + 45/20 = 47/12
   In mixed form: 311/12

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