A random sample of 1500 residential telephones in Phoenix in 1990 found that 387 of the numbers
Question:
A random sample in the same year of 1200 telephones in Scottsdale found that 310 were unlisted.
(a) Find a 95% confidence interval on the difference in the two proportions and use this confidence interval to determine if there is a statistically significant difference in proportions of unlisted numbers between the two cities.
(b) Find a 90% confidence interval on the difference in the two proportions and use this confidence interval to determine if there is a statistically significant difference in proportions of unlisted numbers between the two cities.
(c) Suppose that all the numbers in the problem description were doubled. That is, 774 residents out of 3000 sampled in Phoenix and 620 residents out of 2400 in Scottsdale had unlisted phone numbers. Repeat parts (a) and (b) and comment on the effect of increasing the sample size without changing the proportions on your results.
Fantastic news! We've Found the answer you've been seeking!
Step by Step Answer:
P 387 n1 1500 P1P P1 P1P2 Za2 n n a Za2 20025 196 c P1 0258 P X1 n 025802583 196 00335 P...View the full answer
Answered By
JAPHETH KOGEI
Hi there. I'm here to assist you to score the highest marks on your assignments and homework. My areas of specialisation are:
Auditing, Financial Accounting, Macroeconomics, Monetary-economics, Business-administration, Advanced-accounting, Corporate Finance, Professional-accounting-ethics, Corporate governance, Financial-risk-analysis, Financial-budgeting, Corporate-social-responsibility, Statistics, Business management, logic, Critical thinking,
So, I look forward to helping you solve your academic problem.
I enjoy teaching and tutoring university and high school students. During my free time, I also read books on motivation, leadership, comedy, emotional intelligence, critical thinking, nature, human nature, innovation, persuasion, performance, negotiations, goals, power, time management, wealth, debates, sales, and finance. Additionally, I am a panellist on an FM radio program on Sunday mornings where we discuss current affairs.
I travel three times a year either to the USA, Europe and around Africa.
As a university student in the USA, I enjoyed interacting with people from different cultures and ethnic groups. Together with friends, we travelled widely in the USA and in Europe (UK, France, Denmark, Germany, Turkey, etc).
So, I look forward to tutoring you. I believe that it will be exciting to meet them.
2+ Reviews
10+ Question Solved
Related Book For 
Applied Statistics And Probability For Engineers
ISBN: 9781118539712
6th Edition
Authors: Douglas C. Montgomery, George C. Runger
Question Posted:
