Question

In 2008 the Better Business Bureau settled 80% of complaints it received (USA Today, March 2, 2009). Suppose you have been hired by the Better Business Bureau to investigate the complaints it received this year involving new car dealers. 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. Assume the population proportion of complaints settled for new car dealers is 0.8, the same as the overall proportion of complaints settled in 2008. Round your answers to four decimal places. a. Suppose you select a sample of 450 complaints involving new car dealers. Show the sampling distribution of p. The distribution is - Select your answer -normalnot normal Mean = = b. Based upon a sample of 450 complaints, what is the probability that the sample proportion will be within .04 of the population proportion? c. Suppose you select a sample of 200 complaints involving new car dealers. Show the sampling distribution of p. In determining your answer, use the standard error found in part a. and the probability found using the tables in the text. The distribution is - Select your answer -normalnot normal Mean = = d. Based upon the smaller sample of only 200 complaints, what is the probability that the sample proportion will be within .04 of the population proportion? e. As measured by the increase in probability, how much more precise is the result, when you use a sample of 450 instead of a sample of 200?

Answer 1

(e) The probability of the example extent being inside .04 of the populace mean was diminished from .9624 to .8354. So there is an addition in exactness by expanding the example measure from 200 to 450. In the event that the additional expense of utilizing the bigger example measure isn't excessively incredible, we ought to most likely do as such.