A cost accountant wishes to establish the average amount, , spent ...

[jjjetplane]

A cost accountant wishes to establish the average amount, , spent by executives per day on travel and lodging. The population standard deviation  = 29 . The accountant wants to be 90-percent confident that the estimate, x, obtained is within 7 of the true mean. How large a sample is needed if the company employs 263 executives?

Question 2

Texas passed a law requiring drivers and passengers in the front seat to wear seat belts. In order to estimate the compliance with the law an unmarked car will operate in a selected county and the officer will observe whether or not seat belts are in use. The proportion complying, , in the county is to be estimated by randomly selecting the cars to examine. A confidence coefficient of 0.98 is desired with the estimate, p, to be within 0.05 of the true proportion. How many cars are needed in this sample?

[essyface1]

Answer to Question 1

40

Answer to Question 2

542