Question

A survey of all medium and large sized corporations showed that 50% of them offer retirement plans to their employees. Let ?̂be the proportion in a random sample of 100 such corporations that offer retirement plans to their employees. Find:

(a) the mean and standard deviation of the sampling distribution of ?̂; i.e., ??̂ =? and ??̂ =?

(b) the probability that the value of ?̂is between 0.45 and 0.55; i.e., ?(0.45 ≤ ?̂≤ 0.55)

Answer #1

A survey of all medium- and large-sized corporations showed that
70% of them offer retirement plans to their employees. Let p^ be
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offer retirement plans to their employees. Find the probability
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Round your answer to four decimal places.
P(0.62<p^<0.64)= Enter your answer in accordance to the
question statement

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