Answers

Add 15/42 and 30/84

15/42 + 30/84 is 5/7.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 84 is 84
   
   Next, find the equivalent fraction of both fractional numbers with denominator 84
2. For the 1st fraction, since 42 × 2 = 84,
   15/42 = 15 × 2/42 × 2 = 30/84
3. Likewise, for the 2nd fraction, since 84 × 1 = 84,
   30/84 = 30 × 1/84 × 1 = 30/84
4. Add the two like fractions:
   30/84 + 30/84 = 30 + 30/84 = 60/84
5. 60/84 simplified gives 5/7
6. So, 15/42 + 30/84 = 5/7

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