. Four buses carrying 170 students from the same school arrive at a football stadium. The buses carry, respectively, 50, 45, 40, and 35 students. One of the students is randomly selected. Let X denote the number of students that were on the bus carrying the randomly selected student (including that student). One of the 4 bus drivers is also randomly selected. Let Y denote the number of students on her bus. (a) Compute E[X] and E[Y ]. (b) Compute Var(X) and Var(Y ).

. Four buses carrying 170 students from the same school arrive at a football stadium. The buses carry, respectively, 50, 45, 40, and 35 students. One of the students is randomly selected. Let X denote the number of students that were on the bus carrying the randomly selected student (including that student). One of the 4 bus drivers is also randomly selected. Let Y denote the number of students on her bus. (a) Compute E[X] and E[Y ]. (b) Compute Var(X) and Var(Y ).

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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