A large group of students took a test in Physics and the final grades have a mean of 70 and a standard deviation of 10. The passing score is 60. The distribution is approximately normal. Using the 68-95-99.7 (empirical) rule, find the percentage of the students (a) scored between 60 and 80. (b) scored between 50 and 90. (c) higher than 80. (d) should pass the test.

A large group of students took a test in Physics and the final grades have a mean of 70 and a standard deviation of 10. The passing score is 60. The distribution is approximately normal. Using the 68-95-99.7 (empirical) rule, find the percentage of the students (a) scored between 60 and 80. (b) scored between 50 and 90. (c) higher than 80. (d) should pass the test.

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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