Respuesta :
Answer:
[tex] z = \frac{35.6-35}{\frac{5}{\sqrt{280}}}= 2.007[/tex]
[tex] p_v = P(z>2.007) = 0.0224[/tex]
Since the p value is lower than the significance level given of 0.05 we have enough evidence to reject the null hypothesis on this case. And the best conclusion for this case is:
We (reject) the null hypothesis. That means that we (found) evidence to support the alternative.
Step-by-step explanation:
We have the following info given:
[tex]\bar X = 35.6[/tex] represent the sampel mean for the age of customers
[tex]\sigma = 5[/tex] represent the population standard deviation
[tex]n = 280[/tex] represent the sample size selected
We want to test if the mean age of her customers is over 35 so then the system of hypothesis for this case are:
Null hypothesis: [tex]\mu \leq 35[/tex]
Alternative hypothesis [tex]\mu >35[/tex]
The statistic for this case is given by:
[tex] z = \frac{\bar X -\mu}{\frac{\sigma}{\sqrt{n}}}[/tex]
And replacing the data given we got:
[tex] z = \frac{35.6-35}{\frac{5}{\sqrt{280}}}= 2.007[/tex]
We can calculate the p value since we are conducting a right tailed test like this:
[tex] p_v = P(z>2.007) = 0.0224[/tex]
Since the p value is lower than the significance level given of 0.05 we have enough evidence to reject the null hypothesis on this case. And the best conclusion for this case is:
We (reject) the null hypothesis. That means that we (found) evidence to support the alternative.