- A30
- B31
- C15
- D29
Step-by-Step Solution
The first n natural numbers have sum n(n + 1)/2, so their mean is (n + 1)/2. Setting (n + 1)/2 = 15.5 gives n + 1 = 31 and n = 30.
Answer: A) 30
The mean of the first n natural numbers is 15.5. Find n.
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