# Ba 555 Practice Midterm

1465 WordsFeb 6, 20136 Pages

BA 555 Practical Business Analysis
Practice Midterm Examination
1. Re-do all problems in Practice Problem Set 1.
2. Dollar Car Rental Co. was originally named Dollar a Day Car Rental because they charged $1.00 per day to rent a car, plus a charge per mile driven. Many customers complained that the odometers on Dollar’s cars recorded more miles than were actually driven. To evaluate these complaints you take a random sample of 6 Dollar’s cars, drive them on a carefully measured 100-mile course, and record the miles driven as registered by the odometers. The results are 100, 105, 109, 102, 107, and 101, with the sample standard deviation around 3.578. a. Using these sample results, construct a 95% confidence interval for the*…show more content…* Given the information above, what is [pic] and [pic] for this comparison? Also, does this represent a one-tailed or a two-tailed test? Explain your answer. b. Using a 1% level of significance, is there sufficient evidence for Q-Mart to conclude that customers who use the Q-Mart card charge, on average, more than those who use another charge card? Explain your answer.
9. Suppose that you were asked to test H0: μ = 10 versus Ha: μ > 10 at the [pic] = 0.05 significance level and with a sample of size n = 10. Furthermore, suppose that you observed values of the sample mean and sample standard deviation and concluded that H0 be rejected. Is it true that you might fail to reject H0 if you were to observe the same values of the sample mean and standard deviation from a sample with n > 10? Why