The average age of vehicles registered in the United States is 96 months. Assume the population is normally distributed with a standard deviation of 15 months. Find the probability that the mean age of a sample of 36 vehicles is between 98 and 100 months? Select one: a. 5.2% b. 28.8% c. 15.7% d. 6.4% e. Cannot be determined
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The standard error is the standard deviation divided by the square root of the sample size. In this case, the standard deviation is 15 months and the sample size is 36 vehicles. So, the standard error is 15/√36 = 2.5 months. Show more…
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