Question 1
Heights of adult women in the United States are normally distributed with a population mean of μ = 63.5 inches and a population standard deviation of σ = 2.5. A medical researcher is planning to select a large random sample of adult women to participate in a future study. What is the standard value, or z-value, for an adult woman who has a height of 68.5 inches?
Question 2
An automobile manufacturer introduces a new model that averages 27 miles per gallon in the city. A person who plans to purchase one of these new cars wrote the manufacturer for the details of the tests, and found out that the standard deviation is 3 miles per gallon. Assume that in-city mileage is approximately normally distributed.
What is the probability that the person will purchase a car that averages less than 20 miles per gallon for in-city driving?
What is the probability that the person will purchase a car that averages between 25 and 29 miles per gallon for in-city driving?
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