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Twenty percent of american households own three or more cars. a random sample of 144 american households is selected. let x be the number of households selected that own three or more cars. using the normal approximation, the probability that at least 34 of the households selected own at least three or more cars is

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User Jnoss
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2 votes

Answer:

The probability is 0.163

Step-by-step explanation:

We will use the normal approximation formula for the calculation. If we have that p = 0.20, n = 144, x = 34. We will use Excel to perform the calculation:

If P(x at least 34) = 1 - P(33 or less)

using the binomial formula we have to:

P(x at least 34) = 1 - binomcdf(n,p,largest x value) = 1 - binomcdf(144,0.2,33) = 0.163

User Jwilleke
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