7-6. Before spending huge sums to advertise to car owners that they should fill their tires with nitrogen, it would be wise to conduct a surveyto determine the percentage of car owners who would pay for the nitrogen. How many randomly selected car owners should be surveyed? Assume that we want to be 90% confident that the sample percentage is within 5 percentage points of the true percentage of all car owners would be willing to pay for the nitrogen.
This solution goes through how to calculate sample size required for a random survey.