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In: Statistics and Probability

2. You know that the height of all students is normal with a mean of 69...


2. You know that the height of all students is normal with a mean of 69 inches and a standard deviation of 3 inches.
a) What proportion of all students have a height between 68 and 70.5 inches?
b) What is the 95th (and 99th) percentile of all students’ heights?
c) If you took a sample of 25 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 students is between 68 and 70.5 inches?

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orchestra answered 2 years ago
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