Answer:
The required probability is 0.0855
Step-by-step explanation:
Consider the provided information.
The daily revenue has mean $7200 and standard deviation $1200.
[tex]\mu_{\bar x}=7200[/tex]
[tex]\sigma=1200[/tex]
The daily revenue totals for the next 30 days will be monitored.
[tex]\sigma_{\bar x}=\frac{\sigma}{\sqrt{n}}[/tex]
[tex]\sigma_{\bar x}=\frac{1200}{\sqrt{30}}=219.089[/tex]
As we know [tex]Z=\frac{\bar x-\mu_{\bar x}}{\sigma_{\bar x}}[/tex]
Substitute [tex]\bar x=7500, \mu_{\bar x}=7200\ and\ \sigma_{\bar x}=219.089[/tex] in above formula.
[tex]Z=\frac{7500-7200}{219.089}=1.3693[/tex]
From the standard normal table P( Z >1.3693) = 0.0855
Hence, the required probability is 0.0855