Question

A corporation that maintains a large fleet of company cars for the use of its sales staff is interested in the mean distance driven monthly per sales person. The following table gives the monthly distances in miles driven by a random sample of 17 sales persons: 2035, 2441, 2225, 2078, 2097,2464, 222, 2353,2567, 2621, 1874,2399,2502, 2299, 2011, 2327, 2266 Based on this sample, find a 95% confidence interval for the mean number of miles driven monthly by members of the sales staff, assuming that monthly driving distances are normally distributed. Then complete the table below. Carry your intermediate computations to at least three decimal places. Round your answers to one decimal place. (if necessary, consult a list of formulas.) What is the lower limit of the confidence interval? What is the upper limit of the confidence intervall

Answer 1

ΣX= 388| 89 29799 | Sample size, n = (7 38811 2283 Sample mean, X \7 Sample standard deviation, Ex-n2 Y 1-u 89297991- 17(2283) |- £\ 43279.875 degrees of freedom = n-1 = 17-1 = 16. O.05 significance leNel, d l-0.95 2.1199 criticak valua, ta/

: . The 951. con fiden ce interva ヌ王 tan 43279 875 2283 2.1\99 (2176082 , 23 89.917) (2176 1, 2389.9) Lowe limit of confidence intewal 2.176 1 Upper limit of con fidence intervah 23 89.9