Many people think that a national lobby’s successful fight a…

Many people think that a national lobby’s successful fight against gun control legislation is reflecting the will of a minority of Americans. A random sample of 4000 citizens yielded 2250 who are in favor of gun control legislation. Estimate the true proportion of all Americans who are in favor of gun control legislation using a 90% confidence interval. Express the answer in the form

In 2010, the mean expenditure for auto insurance in a certai…

In 2010, the mean expenditure for auto insurance in a certain state was $806. An insurance salesperson in this state believes that the mean expenditure for auto insurance is less today. She obtains a simple random sample of 32 auto insurance policies and determines the mean expenditure to be $781 with a standard deviation of $39.13.  (a) What are the null and alternative hypotheses? (b)  If the calculated P-value = 0.0005, is there enough evidence to support the claim that the mean expenditure for auto insurance is less than the 2010 amount at the α = 0.05 level of significance?