If \(f(n)= 1 + 2 + 3 +\cdots+(n+1) \) and \(g(n)= \sum_{k=1}^{k=n} \dfrac{1}{f(k)}\), then the least value of \(n\) for which \(g(n)\) exceeds the value \(\dfrac{99}{100}\) is:
Question and options
If and , then the least value of for which exceeds the value is:
- 198
- 99
- 200
- 199
Answer and explanation
Correct answer: D - 199
The least value of is 199. Since , its reciprocal is , and the sum telescopes to . Exceeding requires , hence . At 198 the sum merely equals the threshold.
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