6. From experience, a professor knows that the test scoreof students taking a final examination is a random variable with mean 65. A.Give an upper bound on the probability that a student's test score will exceed 75. B. Suppose in addition the professor knows that the variance of a student's test score isequal to 30. What can be said about the probability that a student will score between55 and 75? C. How many students would have to take the examination so as to ensure,with probabilityat least 0.8, that the class average would be within 5 of 65?

6. From experience, a professor knows that the test scoreof students taking a final examination is a random variable with mean 65. A.Give an upper bound on the probability that a student's test score will exceed 75. B. Suppose in addition the professor knows that the variance of a student's test score isequal to 30. What can be said about the probability that a student will score between55 and 75? C. How many students would have to take the examination so as to ensure,with probabilityat least 0.8, that the class average would be within 5 of 65?

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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