There are 47 students in an elementary statistics class. On the basis of years of experience, the instructor knows that the time needed to grade a randomly chosen firstexamination paper is a random variable with an expected value of 5 min and a standard deviation of 4 min. (Round your answers to four decimal places.)In USE SALT(a) If grading times are independent and the instructor begins grading at 6:50 P.M. and grades continuously, what is the (approximate) probability that he is throughgrading before the 11:00 P.M. TV news begins?(b) If the sports report begins at 11:10, what is the probability that he misses part of the report if he waits until grading is done before turning on the TV?

Solution-: Let, X- be the random variable Given: n=47, E(X)=5,SD=4 We want to find, (a)…

Answered: There are 47 students in an elementary…

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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