You may need to use the appropriate appendix table or technology to answer this question. A government agency provides the number of miles that residents of the 75 largest metropolitan areas travel per day in a car. Suppose that for a simple random sample of 50 City A residents the mean is 22.5 miles a day and the standard deviation is 8.8 miles a day, and for an independent simple random sample of 40 City B residents the mean is 18.3 miles a day and the standard deviation is 7.8 miles a day. (a) What is the point estimate of the difference between the mean number of miles that City A residents travel per day and the mean number of miles that City B residents travel per day? (Use City A - City B.) mi/day (b) What is the 95% confidence interval for the difference between the two population means (in miles per day)? (Use City A - City B. Round your answers to one decimal place.) mi/day to mi/day Need Help? Read It Watch It