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I need help with this question: Choose an American household at random. What is the expected number of cars for that household. Table: Number of cars, 0, 1,2, 3, 4, 5Probability: 0.09, 0.36, 0.35, 0.13, 0.05, 0.02

User Dextrey
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ANSWER

1.75

Step-by-step explanation

The expected value of a discrete random variable X is,


E\lbrack X\rbrack=\sum x_iP(x_i)

In this case, to find the expected number of cars for the household, we have to add all numbers of cars multiplied by their probabilities,


E\lbrack X\rbrack=0\cdot0.09+1\cdot0.36+2\cdot0.35+3\cdot0.13+4\cdot0.05+5\cdot0.02=1.75

Hence, the expected number of cars in the household is 1.75.

User Matias Nino
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