Question

SelTCRE The speeds of vehicles traveling on a highway are normally distributed with an unknown population mean and standard deviation. A random sample of 11 vehicles is taken and results in a sample mean of 65 miles per hour and sample standard deviation of 9 miles per hour. 301 df toe tees to.025 0.01 0.005 9 10 11 12 13 1.383 1.372 1.363 1.356 1.350 1.833 2.262 1.812 2.228 1.796 2.201 1.782 2.179 1.771 2.160 2.821 3.250 2.764 3.169 2.718 3.106 2.681 3.055 2.650 3.012 Find a 90% confidence interval estimate for the population mean using the Student's f-distribution • Round the final answers to two decimal places. Provide your answer below: 97% of the values lie between and no QUESTIONS. 1 POINT Suppose the number of pages per book in a library has an unknown distribution with population mean 327 and population standard deviation 35. A sample of size 90 is randomly taken from the population, and the sum of the values is taken Using the Central Limit Theorem for Sums, what is the standard deviation for the sample sum distribution? Round your answer to two decimal places. Provide your answer below: The average American city has 50 buses that use green energy, with a standard deviation of 5 buses. A city planner is interested in the sample mean number of buses for a sample of 30 cities. He calculates that Max 130 = 9.13 and 0:= 190 = 0.91 What did he do wrong? Select the correct answer below: He didn't do anything wrong. The correct answer is = 9.13 and 0 = 0.91 He had the N = 50 and a wrong, but calculated a correctly. He should have had: = 0.91. O He unnecessarily divided Hi = 9.13 and 1 = 5 by vi and should have had: He did not need to divide a oro by V, and should have had: AL = 50 and oi = 5

Answer 1