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In 2016, the better business bureau settled 76 % of complaints they received in the united states.
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Suppose you have been hired by the better business bureau to investigate the complaints they received this year involving new car dealers.
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You plan to select a sample of new car dealer complaints to estimate the proportion of complaints the better business bureau is able to settle.
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Assume the population proportion of complaints is 0 .76, the same as the overall proportion of complaints settled in 2016.
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So we're going to start with a sample size of 200, and we're going to show, for part a, our sampling distribution of p, which is 0 .76, and we're going to show our standard deviation, and we calculate that by taking 0 .76 times 0 .24, which is 1 minus 0 .76, divided by 200.
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Gives us .0302 for our standard deviation.
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So for part b, we want to find the probability that the sample proportion will be within 0 .04 of the population proportion.
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So we're doing the probability that we will be within negative 4 and positive.
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And when i say 4, i should say 0 .0 4 of the sample mean.
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Now i'm going to go ahead and switch some things out here, because we're going to divide this by our standard deviation...