Question 1079953
68–95–99.7 rule tells us the percentage of values that lie around the mean in a normal distribution with a width of one, two and three standard deviations
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a)  74 is two standard deviations from the mean, therefore 34 percent + 13.5 percent = 47.5 percent.  Note that we had to take half of 68 percent and half of (95 percent - 68 percent).
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b)  2.5 percent is approximately 2 standard deviations from the mean, therefore 2 * 2.5 = 5 and 69 - 5 = 64 inches
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c)  the middle 95 percent of men fall between 2 standard deviations of the mean,  therefore the middle 95 percent is 64 to 74 inches
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