The scores on a placement test given to college freshmen for the past five years are approximately normally distributed with a mean μ = 74 and a variance σ^2 = 8. Would you still consider σ^2 = 8 to be a validvalue of the variance if a random sample of 20 students who take the placement test this year obtain a value ofs^2 = 10?

The scores on a placement test given to college freshmen for the past five years are approximately normally distributed with a mean μ = 74 and a variance σ^2 = 8. Would you still consider σ^2 = 8 to be a validvalue of the variance if a random sample of 20 students who take the placement test this year obtain a value ofs^2 = 10?

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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