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Chapter 6: Q.2.2 (page 370)

A large auto dealership keeps track of sales and leases agreements made during each hour of the day. Let χ= the number of cars sold and γ= the number of cars leased during the first hour of business on a randomly selected Friday. Based on previous records, the probability distributions of χand γare as follows:

Define τ=χ+γ

Compute στassuming that χ and γ are independent. Show your work.

Short Answer

Expert verified

From the given information, the standard deviation is1.14

Step by step solution

01

Given Information

It is given in the question that,

μχ=1.1σχ=0.943

μγ=0.7σγ=0.64

τ=χ+γ

02

Explanation

The standard deviation of τcan be calculated as:

localid="1649912163260" σT=(0.943)2+(0.64)2=1.2988=1.14

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