Quiz 1 solution

Quiz 1 solution - handling of the economy? see numerator in...

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

View Full Document Right Arrow Icon
ENME 392 Fall 2009 - Statistical Methods for Product and Process Development Tues – Thurs: Section 0101 11:00-12:15 room EGR 2107; Section 0201 9:30-10:45 room ANS 0408 Prof. D. B. Barker, room 2112 ENG, (301) 405-5264, [email protected] 9/17/09 page 1 Quiz #1 – Terms Definitions and Probability Closed Book & Closed Notes 1. A national polling organization conducted a telephone poll of 600 randomly selected senior citizens. Respondents were asked whether they approved or disapproved of President Obama’s handling of the economy. Additionally, the gender of each respondent was noted. The following table reveals the results of the survey: Approve Disapprove Totals Female 220 130 350 Male 105 145 250 Totals 325 275 600 Suppose that the poll data is representative of the senior citizen population. a) What is the probability that a senior citizen is female and approves of the President’s
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: handling of the economy? see numerator in question (b) = 220/600 = 0.367 b) Among those senior citizens that approve of the President’s handling of the economy, what proportion is female? 677 . 325 220 600 325 600 220 ] Pr[ ] AND Pr[ ] | Pr[ = = = = approve approve F approve F c) Among female senior citizens, what proportion approves of the President’s handling of the economy? 629 . 350 220 600 350 600 220 ] Pr[ ] F AND Pr[ ] | Pr[ = = = = F approve F approve d) Is a senior citizen’s opinion of the President’s handling of the economy independent of the citizen’s gender? 583 . 600 350 ] Pr[ 677 . ] | Pr[ = = ≠ = F approve F Hence, the events are dependent. If independent Pr[F | approve] = Pr[F], etc....
View Full Document

This note was uploaded on 02/27/2010 for the course ENME 271 taught by Professor Marks during the Spring '08 term at Maryland.

Ask a homework question - tutors are online