E text problems Week 1

# E text problems Week 1 - 1275 to round it up. Rounding down...

This preview shows page 1. Sign up to view the full content.

Individual Assignment: E-Text (Please complete and submit problems in Microsoft Excel. Show all work for full credit.) Resource: Ch. 8 of Applied Statistics in Business and Economics Prepare answers to the following assignments: Chapter Exercises 8.48 (a) Construct a 95 percent confidence interval for the true mean. x-bar = 346.5 s = 170.378 t-critical value for 95% CI with df=19 = 2.093 E = 2.093*170.378/sqrt(20) = 2.0931.96*38.0976=79.74 95% CI : (346.5-79.74,346.5+79.74) (b) Normality is an issue because the confidence level indicates about the entire population a random sample may not convey the details of the whole population. (c) The sample size needed would be 1271.4
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: 1275 to round it up. Rounding down would cause there to not be enough to have that confidence level. (d) You could decrease the confidence level or you could increase E. (e) Chapter Exercises 8.64 (a)E = z*(p-hat/sqrt(n)) E = 1.645*sqrt[(86/773)(687/773)/773) = 0.01131 90% C.I. = ((86/773)-0.01131 , (86/773)+0.01131) (b) pn= (86/773)773&gt;5; nq=(687/773)773&gt;5 (c) The very quick rule does not apply in this situation because p is .1113 which is very far below .5 (d) This sample may not be accurate as he being a popcorn connoisseur, he may be slightly better at making popcorn at the proper temperature....
View Full Document

## This note was uploaded on 02/21/2011 for the course RES 342 taught by Professor Carey during the Spring '08 term at University of Phoenix.

Ask a homework question - tutors are online