4. The grades of a group of 1000 students in an exam are normally distributed with a mean of 70 and a standard deviation of 10. Astudent from this group is selected randomly.a) Find the probability that his/her grade is greater than 80.b) Find the probability that his/her grade is less than 50.c) Find the probability that his/her grade is between 50 and 80.d) Approximately, how many students have grades greater than 80?

(a) The probability that his/her grade is greater than 80 is,

Answered: 4. The grades of a group of 1000…

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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