We wish to estimate the population mean of a variable that has standard deviation 70.5. we want to estimate it with an error no greater than 5 units with probability 0.99. how big a sample should we take from the population? what happens if the standard deviation and the margin of error are both doubled?

Use the information given below, to compare the cost of operating two different vehicles for one month (4 weeks) you are considering two different cars. you drive to work, a 20 mile round trip, five days a week. gasoline costs you $1.50 per gallon car agets 28 miles per gallon, would have $300 a year in maintenance costs, and would cost you $1,500 per year to insure car b gets 19 miles per gallon, would have $500 a year in maintenance costs, and would cost you $1,000 per year to insure costs car a car b gas cost per month insurance cost per month maintenance cost per month $ total cost per month