View the step-by-step solution to:

# Thanks The mean of the distribution of maximum car mileage is 150,000 miles with a standard deviation of 20,000 miles.

The mean of the distribution of maximum car mileage is 150,000 miles with a standard deviation of 20,000 miles. Assume that the distribution approximates a Bell curve.

a.      Use the z-table calculator and find the maximum mileage for a car which is the 85th percentile. Use value from an area. (Show a screen shot for your answer.)

http://davidmlane.com/hyperstat/z_table.html

b.     What is the z-score for this mileage? z-score = (x-µ)/σ

c.      Suppose you pick a single car at random. What is the probability that the maximum mileage will be between 170,000 and 200,000 miles? Use area from a value. (Show a screen shot for your answer.)

Use the central limit theorem to the following questions.

d.     Suppose you pick a group of 25 cars instead. What would be the standard deviation of the sample's (group's) average? (i.e. σxbar = σ/)

e.      What is the probability that a group of 25 cars will have an average maximum mileage between 170,000 and 200,000 miles? Use the z-table calculator with "area from a value". (Show a screen shot for your answer.)

### Why Join Course Hero?

Course Hero has all the homework and study help you need to succeed! We’ve got course-specific notes, study guides, and practice tests along with expert tutors.

### -

Educational Resources
• ### -

Study Documents

Find the best study resources around, tagged to your specific courses. Share your own to gain free Course Hero access.

Browse Documents