6. Assume the distribution is normal. The mean age of senior citizens who watch more than seven hours of television is 67.1 years, and the standard deviation 7.4 years. Round z-scores to two decimal places and probabilities to four decimal places. a. Assume one senior citizen who watches more than seven hours of television is randomly selected. Find the probability that the person is between 66-years- and 74-years-old. z-values = type your answer... Probability = type your answer... b. Assume 47 senior citizens who watch more than seven hours of television are randomly selected. Find the probability that the mean age is more than 70 years. z-value = type your answer... Probability = type your answer... 6. c. Is it unusual for the mean age of 47 senior citizens who watch television for more than seven hours to be more than 70 years? Explain in one sentence.
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