Questions: (a) Find the P - value for the test statistic z=-1.41 for the following null and alternative hypotheses:
H0: The population mean is 50.
Ha: The population mean is less than 50.
The P - value is
Transcript text: (a) Find the $P$ - value for the test statistic $z=-1.41$ for the following null and alternative hypotheses:
$H_{0}$ : The population mean is 50 .
$H_{a}$ : The population mean is less than 50.
The $P$ - value is
Solution
Solution Steps
Step 1: Define the Hypotheses
We are testing the following hypotheses:
Null Hypothesis \( H_0 \): The population mean is \( \mu = 50 \).
Alternative Hypothesis \( H_a \): The population mean is less than \( 50 \).
Step 2: Calculate the Z-score Range
For the given test statistic \( z = -1.41 \), we define the Z-score range for the left-tailed test:
Lower bound: \( -\infty \)
Upper bound: \( -1.41 \)
Step 3: Calculate the P-value
The P-value is calculated as follows:
\[
P = \Phi(Z_{end}) - \Phi(Z_{start}) = \Phi(-1.41) - \Phi(-\infty)
\]
From the calculations, we find:
\[
P = 0.0793
\]
Final Answer
The P-value for the test statistic \( z = -1.41 \) is \\(\boxed{0.0793}\\).