On a particular freeway in Michigan, it is reported that the proportion of cars that exceed the speed limit is 0.15. Given this information, the probability that a sample of 250 cars will have a sample proportion below 0.12 is approximately .0918.

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Quizplus · Accepted Answer

This is true based on the given information and assuming that the sample of 250 cars is a random sample from the population of cars on the freeway. The probability can be calculated using the normal approximation to the binomial distribution with a mean of 0.15 and a standard deviation of 0.0225, giving a z-score of -1.333. Consulting a standard normal distribution table or using a calculator, the probability of getting a sample proportion below 0.12 is approximately 0.0918.

On a Particular Freeway in Michigan, It Is Reported That