Answer:
The probability of obtaining a sample mean less than or equal to $8.85 per hour=0.0082
Step-by-step explanation:
We are given that
Average wage, [tex]\mu=[/tex]$9.00/hour
Standard deviation,[tex]\sigma=[/tex]$0.50
n=64
We have to find the  probability of obtaining a sample mean less than or equal to $8.85 per hour.
[tex]P(\bar{x} \leq 8.85)=P(Z\leq \frac{\bar{x}-\mu}{\frac{\sigma}{\sqrt{n}}})[/tex]
Using the values
[tex]P(\bar{x}\leq 8.85)=P(Z\leq \frac{8.85-9}{\frac{0.50}{\sqrt{64}}})[/tex]
[tex]P(\bar{x}\leq 8.85)=P(Z\leq \frac{-0.15}{\frac{0.50}{8}})[/tex]
[tex]P(\bar{x}\leq 8.85)=P(Z\leq -2.4)[/tex]
[tex]P(\bar{x}\leq 8.85)=0.0082[/tex]
Hence, the probability of obtaining a sample mean less than or equal to $8.85 per hour=0.0082