A population of students spends an average of $8 a day on dinner. The standard deviation of the expenditure is $4. A simple random sample of 64 students is taken. Be sure to show work.
a. What are the expected value, standard deviation, and shape of the sampling distribution of the sample mean?
b. What is the probability that average spending is more than $9?
c. What is the probability that average spending is between $7 and $9?