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Chapter 6: Q 31. (page 373)

Exercises 31–33 refer to the following setting. Choose an American household at random and

let the random variable X be the number of cars (including SUVs and light trucks) they own.

Here is the probability distribution if we ignore the few households that own more than 5cars:

What’s the expected number of cars in a randomly selected American household?

a)1.00b)1.75c)1.84d)2.00e)2.50

Short Answer

Expert verified

The expected number of cars in a randomly selected American household is1.75(b)

Step by step solution

01

Step 1. Given information 

We have given probability distribution:

02

Step 2. To find the probability.  

The expected value is the sum of the product of the each possibility with its probability.

μ=∑xP(x)=0×0.09+1×0.36+2×0.35+3×0.13+4×0.05+5×0.02=1.75

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