Problem

You wish to test the following claim $\left(H_{a}\right)$ at a significance level of $\alpha=0.10$.
\[
\begin{array}{l}
H_{o}: \mu=78.2 \\
H_{a}: \mu> 78.2
\end{array}
\]

You believe the population is normally distributed and you know the standard deviation is $\sigma=10.5$. You obtain a sample mean of $M=81.1$ for a sample of size $n=62$.

What is the test statistic for this sample? (Report answer accurate to three decimal places.)
\[
\text { test statistic }=
\]

What is the p-value for this sample? (Report answer accurate to four decimal places.)
\[
\mathrm{p} \text {-value }=
\]

The $p$-value is...
- less than (or equal to) $\alpha$

Answer

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Answer

The test statistic is \( \boxed{2.175} \)

Steps

Step 1 :Calculate the test statistic using the formula \( z = \frac{\bar{x} - \mu}{\frac{\sigma}{\sqrt{n}}} \)

Step 2 :Plug in the given values: \( \bar{x} = 81.1 \), \( \mu = 78.2 \), \( \sigma = 10.5 \), and \( n = 62 \)

Step 3 :Compute the test statistic: \( z = \frac{81.1 - 78.2}{\frac{10.5}{\sqrt{62}}} \)

Step 4 :The test statistic is \( \boxed{2.175} \)

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