The scores on a test are normally distributed with an average (mean) of 72 and a standard deviation of 4 points. A. What is the probability that a test score is greater than 80? B. What is the probability that a test score is less than 67? C. What is the probability that a score is between 70 and 80? D. What score is the grade at which 10% of scores are lower than other scores?

The scores on a test are normally distributed with an average (mean) of 72 and a standard deviation of 4 points. A. What is the probability that a test score is greater than 80? B. What is the probability that a test score is less than 67? C. What is the probability that a score is between 70 and 80? D. What score is the grade at which 10% of scores are lower than other scores?

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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