Step 1 :Identify the null and alternative hypotheses. The null hypothesis \(H_{0}\) is that the population mean \(\mu\) is equal to 3.75. The alternative hypothesis \(H_{1}\) is that the population mean \(\mu\) is not equal to 3.75. So, we have: \[ \begin{array}{l} H_{0}: \mu=3.75 \ H_{1}: \mu \neq 3.75 \end{array} \]
Step 2 :Calculate the test statistic. The test statistic (z) is calculated using the formula \(z = \frac{\bar{x} - \mu_{0}}{s / \sqrt{n}}\), where \(\bar{x}\) is the sample mean, \(\mu_{0}\) is the population mean under the null hypothesis, s is the sample standard deviation, and n is the sample size. Substituting the given values, we get \(z = \frac{3.58 - 3.75}{0.63 / \sqrt{96}}\), which gives \(z \approx -2.64\).
Step 3 :Calculate the P-value. The P-value is calculated using the cumulative distribution function (CDF) of the standard normal distribution. For a two-tailed test, we multiply the result by 2. The P-value is approximately 0.008.
Step 4 :Compare the P-value with the significance level. The P-value (0.008) is less than the significance level (0.05), so we reject the null hypothesis.
Step 5 :State the final conclusion. Since we rejected the null hypothesis, we conclude that the population mean is not equal to 3.75. Therefore, the final answer is: The test statistic is \(\boxed{-2.64}\) and the P-value is \(\boxed{0.008}\). We reject the null hypothesis and conclude that the population mean is not equal to 3.75.