Questions: Choose the formula that is used to find the test statistic for a mean when the population standard deviation is unknown.
t = (x̄ - μ) / (s / √n)
z = (x̄ - μ) / (θ / √n)
z = (x̄ c - μ1) / (b / √n)
z = (χ - μ) / σ
Transcript text: Choose the formula that is used to find the test statistic for a mean when the population standard deviation is unknown.
$\mathrm{t}=\frac{\overline{\mathrm{x}}-\mu}{\frac{\mathrm{s}}{\sqrt{n}}}$
$\mathrm{z}=\frac{\overline{\bar{x}}-\mu}{\frac{\theta}{\sqrt{n}}}$
$z=\frac{\bar{x} c-\mu 1}{\frac{b}{\sqrt{n}}}$
$\mathrm{z}=\frac{\chi-\mu}{\sigma}$
Solution
Solution Steps
Step 1: Calculate the Standard Error
The standard error SE is calculated using the formula:
SE=ns=3010≈1.8257
Step 2: Calculate the Test Statistic
The test statistic t is calculated using the formula:
t=SExˉ−μ0=1.825750−45≈2.7386
Step 3: Calculate the P-value
For a two-tailed test, the p-value P is calculated as:
P=2×(1−T(∣t∣))≈0.0062
Final Answer
The test statistic is t≈2.7386 and the p-value is P≈0.0062.