Answer: Choice C)
n = 25
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Explanation:
The standard error formula for the mean is
[tex]\sigma_{M} = \frac{\sigma}{\sqrt{n}}\\\\[/tex]
Since we want this 2.00 or less, this means,
[tex]\sigma_{M} \le 2.00\\\\\frac{10}{\sqrt{n}} \le 2.00\\\\10 \le 2.00\sqrt{n}\\\\2.00\sqrt{n} \ge 10\\\\\sqrt{n} \ge \frac{10}{2.00}\\\\\sqrt{n} \ge 5\\\\n \ge 5^2\\\\n \ge 25\\\\[/tex]
The sample size needs to be n = 25 or larger.
In other words, the sample size needs to be at least 25.
