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In: Statistics and Probability

You know that the height of all Sy Syms students is normal with a mean of...

You know that the height of all Sy Syms students is normal with a mean of 69 inches and a standard deviation of 3 inches.
a) What proportion of all Sy Syms students have a height between 68 and 70.5 inches?
b) What is the 95th (and 99th) percentile of all Sy Syms students’ heights?
c) If you took a sample of 25 Sy Syms students and measured their heights, what would you expect the average, variance and standard deviation of all possible sample means to be?
d) What is the probability that the sample mean height of the 25 Sy Syms students is between 68 and 70.5 inches?

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