問題詳情

10. Suppose that the mean daily TV viewing time per household follows a normal distribution with amean of 5 hours and a standard deviation of 2 hours. Which of the following is/are correct?
(A) Theprobability that a household views TV more than 3 hours a day is 0.1587;
(B) The probability that ahousehold views TV between 4-7 hours a day is 0.5328;
(C) In order to be in the bottom 10% of allTV viewing households, a household has to view TV for less than 2.44 hours a day;
(D) Among agroup of households that all members are obese (BMI>=35), we randomly selected a sample of 16households to investigate whether the mean of their TV viewing time is longer than that of thepopulation mean. We found that the sample mean was 6.5 hours. To conduct a one-tailed z-test witha-0.05, the z-score=3.
(E) From ( D ), we can conclude that households with all obese members havelonger TV viewing time than the population with the p-value=0.0013, based on the one-tailed z-test.

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