Answer to Question #307854 in Statistics and Probability for ida

Question

In order to test the proportion of smokers who agree with the prohibition of smoking in public buildings, a researcher takes a random sample of 500 smokers. He found that 155 of them agree that smoking should not be allowed in public buildings.

 a)     Write the formula for 1-∞(100%) confidence interval for the true proportion.

 b)     Calculate the size of maximum error for the 99% confidence interval.

 c)     Obtain a 99% confidence interval for the population proprotion of smokers who think that smoking should not be allowed in public buildings.

A publishing company published a reference book and collected information on the prices of 16 similar reference books in order to determine an appropriate price for its book. The sample gives mean RM 70.50 and standard deviation RM 4.50. Assume the price is normally distributed.

a)     Suppose x is chosen as a point estimate for the population mean. Show that this estimator is unbiased.

  b)     Determine the sampling distribution for the sample mean, x.