What is the smallest positive integer $n$ such that, out of the $n$ unit fractions $\frac{1}{k}$ where $1 \le k \le n$, exactly half of the fractions give a terminating decimal?
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<|im_start|>user
What is the smallest positive integer $n$ such that, out of the $n$ unit fractions $\frac{1}{k}$ where $1 \le k \le n$, exactly half of the fractions give a terminating decimal?
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user
12
What is the smallest positive integer $n$ such that, out of the $n$ unit fractions $\frac{1}{k}$ where $1 \le k \le n$, exactly half of the fractions give a terminating decimal?
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