The state of Virginia shows than automobile is driven an average 23,500 km/year with a stand...

The state of Virginia shows than automobile is driven an average 23,500 km/year with a stand deviation of 3900 kilometers. Assume the distribution of measurements is approximately normal.

a) What is the probability that a randomly selected automobile is found to have driven at most 25,000km/yr?

b) What is the probability that a randomly selected automobile is found to have driven between 20,000 and 30,000 km/yr?)

c) Solve for the third quartile.

d) Suppose that the average cost of leasing a car is $300 per month with a standard deviation of $110. You are interested in leasing a car and decide to investigate the market. You randomly sample 30 people among your acquaintances that are currently leasing. What is the probability that among those 30 people the sample mean is less than $260?

e) What is the probability that among the 30 people sampled in part d) the sample mean is greater than $330?

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Expert Solution

orchestra answered 11 months ago

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