8-76. According to an investigative reporter (Jim Drinkard – Legislators want to Ground ‘Fact-finding’ Trips, USA Today, January 2006), members of Congress are coming under scrutiny for ‘fact-finding’ trips. Since 2000, members of Congress have made 6,666 trips paid for by private interests. The trips were worth about $19.6 million.
a. Calculate the average cost of these fact finding trips.
b. If the cost of the trips could be considered to have a normal distribution, determine the standard deviation of the cost of the trips. (Hint: Recall the Empirical Rule).
c. Choose a reasonable confidence level and calculate a confidence interval for the average cost of congressional fact-finding trips from the year 2000 until January 19, 2006.