Answers

Add 42/84 and 45/70

42/84 + 45/70 is 8/7.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 84 and 70 is 420
   
   Next, find the equivalent fraction of both fractional numbers with denominator 420
2. For the 1st fraction, since 84 × 5 = 420,
   42/84 = 42 × 5/84 × 5 = 210/420
3. Likewise, for the 2nd fraction, since 70 × 6 = 420,
   45/70 = 45 × 6/70 × 6 = 270/420
4. Add the two like fractions:
   210/420 + 270/420 = 210 + 270/420 = 480/420
5. 480/420 simplified gives 8/7
6. So, 42/84 + 45/70 = 8/7
   In mixed form: 11/7

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