Jobs and productivity! How do banks rate? One way to answer this question is to examine annual profits per employee. The following is data about annual profits per employee (in units of 1 thousanddollars per employee) for representative companies in financial services. Assume ? ? 9.9 thousanddollars.
54.4 | 45.3 | 48.8 | 60.0 | 31.3 | 39.0 | 29.9 | 44.6 | 42.5 | 33.0 | 33.6 |
36.9 | 27.0 | 47.1 | 33.8 | 28.1 | 28.5 | 29.1 | 36.5 | 36.1 | 26.9 | 27.8 |
28.8 | 29.3 | 31.5 | 31.7 | 31.1 | 38.0 | 32.0 | 31.7 | 32.9 | 23.1 | 54.9 |
43.8 | 36.9 | 31.9 | 25.5 | 23.2 | 29.8 | 22.3 | 26.5 | 26.7 |
(a) Use a calculator or appropriate computer software to find
xfor the preceding data. (Round your answer to two decimal
places.)
_______ thousand dollars
(b) Let us say that the preceding data are representative of the
entire sector of (successful) financial services corporations. Find
a 75% confidenceinterval for ?, the average annual profit
per employee for all successful banks. (Round your answers to two
decimal places.)
lower limit _____ | thousand dollars |
upper limit _____ | thousand dollars |
(c) Find a 90% confidence interval for ?, the average annual profit per employee for all successful banks. (Round your answers to two decimal places.)
lower limit _____ | thousand dollars |
upper limit _____ | thousand dollars |
(a)
Following is the average of the given data calculated by excel;
(b)
For 75% confidence interval, using excel function "=NORMSINV(0.875)", critical value of z is . So required confidence interval is
Lower limit: 32.81 thousand dollars
Upper limit: 36.33 thousand dollars
(b)
For 90% confidence interval, using excel function "=NORMSINV(0.95)", critical value of z is . So required confidence interval is
Lower limit: 32.06 thousand dollars
Upper limit: 37.08 thousand dollars
Get Answers For Free
Most questions answered within 1 hours.