Question

(20 points, 4 each) An engineering study of a city rated all the thousands of buildings within the city limits for flood resilience. The results showed a normal distribution with a mean p-20.6 and a standard deviation of o = 6.3. a. What is the probability that a randomly selected building received a score of 23 or higher? (Hint: we are talking about a specific building, and not-for example-a sample mean!) b. What is the distribution of the sample mean, when 25 samples are taken? (Please report in N-(H, o, or in words, "the sample mean is normally distributed with..." c. Of a sample of 25 buildings, what is the probability that the mean score (X) is 23 or d. Ifa sample of 25 buildings is taken, what is the probability that the study reports an average building performance within 4 points of the mean? e. How about if 50 sample points are taken? higher?

Answer 1

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