Answer:
[tex](a)\ \mu_y = 1125[/tex]
[tex](b)\ \sigma_y = 300[/tex]
Step-by-step explanation:
Given
[tex]\mu_x = 75[/tex] -- Mean of T-shirts
[tex]\sigma_x = 20[/tex] -- Standard deviation of T-shirts
[tex]Rate = \$ 15[/tex]
Solving (a): The mean of the revenue [tex](\mu_y)[/tex]
To solve this, we use:
[tex]\mu_y = Rate * \mu_x\\[/tex]
This gives:
[tex]\mu_y = 15 * 75[/tex]
[tex]\mu_y = 1125[/tex]
Solving (b): The standard deviation of the revenue [tex](\sigma_y)[/tex]
To solve this, we use:
[tex]\sigma_y = \sqrt{Rate^2 * \sigma_2^2}[/tex]
This gives:
[tex]\sigma_y = \sqrt{15^2 * 20^2}[/tex]
[tex]\sigma_y = \sqrt{90000}[/tex]
[tex]\sigma_y = 300[/tex]