Problem

Use technology to help you test the claim about the population mean, $\mu$, at the given level of significance, $\alpha$, using the given sample statistics. Assume the population is normally distributed.
Claim: $\mu> 1220 ; \alpha=0.04 ; \sigma=195.94$. Sample statistics: $\bar{x}=1243.48, n=300$
\[
H_{a}: \mu> 1 \angle 43.48
\]
E. $H_{0}: \mu \geq 1220$
$H_{a}: \mu< 1220$
\[
\begin{array}{l}
H_{a}: \mu \leq 1 \angle L U \\
H_{0}: \mu> 1243.48 \\
H_{a}: \mu \leq 1243.48
\end{array}
\]
Calculate the standardized test statistic.
The standardized test statistic is 2.08
(Round to two decimal places as needed.)
Determine the P-value.
$\mathrm{P}=$
(Round to three decimal places as needed.)

Answer

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Answer

Final Answer: The standardized test statistic is approximately \(\boxed{2.08}\) and the P-value is approximately \(\boxed{0.019}\).

Steps

Step 1 :Given the sample mean (\(\bar{x}\)) is 1243.48, the population standard deviation (\(\sigma\)) is 195.94, the sample size (n) is 300, and the hypothesized population mean (\(\mu\)) is 1220.

Step 2 :We can use these to calculate the z-score, which is the standardized test statistic. The formula for the z-score is: \[z = \frac{\bar{x} - \mu}{\sigma / \sqrt{n}}\]

Step 3 :Substituting the given values into the formula, we get a z-score of approximately 2.08.

Step 4 :After calculating the z-score, we can use a z-table or a statistical calculator to find the P-value. The P-value is the probability that a z-score is more extreme than the calculated z-score, given that the null hypothesis is true.

Step 5 :The calculated P-value is approximately 0.019, which is less than the given level of significance, \(\alpha=0.04\). This means that we would reject the null hypothesis in favor of the alternative hypothesis.

Step 6 :Final Answer: The standardized test statistic is approximately \(\boxed{2.08}\) and the P-value is approximately \(\boxed{0.019}\).

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