The average age of cars owned by residents of a small city is 6 years with...

The average age of cars owned by residents of a small city is 6 years with a standard deviation of 2.2 years. A simple random sample of 400 cars is to be selected, and the sample mean age of these cars is to be computed. What is the probability that the average age of the 400 cars is more than 6.1 years? Show all main steps of your calculation. (No points will be given to an answer of only a final number provided even if the number is correct.)

Expert Solution

µ = 6

sd = 2.2

n = 400

= P(Z > -0.909)

= 1 - P(Z < -0.909)

= 1 - 0.1817

= 0.8183

orchestra answered 2 years ago

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