Questions: (a) State the null hypothesis (H0) and the alternative hypothesis (H1).
(H0:)
(H1:)
(b) Determine the type of test statistic to use.
(Choose one)
(c) Find the value of the test statistic. (Round to three or more decimal places.)
(d) Find the (p)-value. (Round to three or more decimal places.)
(e) Can we conclude that the mean IQ score of this year's class is greater than that of previous years?
Yes No
Check
Transcript text: (a) State the null hypothesis $H_{0}$ and the alternative hypothesis $H_{1}$.
\[
\begin{array}{l}
H_{0}: \square \\
H_{1}: \square
\end{array}
\]
(b) Determine the type of test statistic to use.
(Choose one)
(c) Find the value of the test statistic. (Round to three or more decimal places.)
$\square$
(d) Find the $p$-value. (Round to three or more decimal places.)
$\square$
(e) Can we conclude that the mean IQ score of this year's class is greater than that of previous years?
Yes No
Check
Solution
Solution Steps
Step 1: State the Hypotheses
The null hypothesis \( H_0 \) and the alternative hypothesis \( H_1 \) are stated as follows:
\[
H_0: \text{The mean IQ score of this year's class is equal to that of previous years } (\mu = 100)
\]
\[
H_1: \text{The mean IQ score of this year's class is greater than that of previous years } (\mu > 100)
\]
Step 2: Determine the Type of Test Statistic
The type of test statistic used for this hypothesis test is a \( t \)-test, as we are dealing with a sample mean and sample standard deviation.
Step 3: Calculate the Test Statistic
The sample mean \( \bar{x} \) is calculated as follows:
\[
\bar{x} = \frac{\sum_{i=1}^N x_i}{N} = \frac{1325}{10} = 132.5
\]
The standard error \( SE \) is calculated using the formula:
\[
SE = \frac{\sigma}{\sqrt{n}} = \frac{15.138}{\sqrt{10}} \approx 4.787
\]
The test statistic \( t \) is then calculated as:
\[
t = \frac{\bar{x} - \mu_0}{SE} = \frac{132.5 - 100}{4.787} \approx 6.789
\]
Step 4: Calculate the p-value
For a right-tailed test, the p-value is calculated as:
\[
P = 1 - T(z) \approx 0.0
\]
Step 5: Conclusion
Since the p-value \( 0.0 \) is less than the significance level \( \alpha = 0.05 \), we reject the null hypothesis. Therefore, we can conclude that the mean IQ score of this year's class is greater than that of previous years.