An English racing team called the Bloodhound Project is testing a rocket car that they hope will break the current land speed record. They expect this hybrid vehicle, which runs on concentrated peroxide and a synthetic rubber, to reach speeds over 1000 mph.49 Suppose a random sample of test runs was obtained, and the speed of the rocket car was recorded for each.
a. Find a 99% confidence interval for the population mean speed of the rocket car.
b. Find a 99% confidence interval for the population variance in speed of the rocket car.
c. What assumptions did you make in constructing these two confidence intervals?
d. The Bloodhound Team members will attempt to break the 1000 mph barrier on the Hakskeen Pan desert in South Africa in 2016. Using the test speed data, is there any evidence to suggest the mean speed of the rocket car will be great than 1000 mph? Justify your answer.
Many businesses rent a limousine to chauffeur important clients to/from an airport, hotel, or office. A random sample of the cost (in dollars) of renting a limousine for the entire day in Cincinnati was obtained. For n 5 25, the mean was x 5 410.25 and the standard deviation was s 5 35.07. Assume the cost distribution is normal.
a. Find a 95% confidence interval for the population mean cost of renting a limousine for the entire day.
b. Find a 95% confidence interval for the population variance in the cost of renting a limousine for the entire day.
c. Find a 95% confidence interval for the standard deviation in the cost of renting a limousine for the entire day