Chapter 8: Problem 3
Which of the following are the same at all levels of output under perfect competition? a. Marginal cost and marginal revenue b. Price and marginal revenue c. Price and marginal cost d. All of the above
Chapter 8: Problem 3
Which of the following are the same at all levels of output under perfect competition? a. Marginal cost and marginal revenue b. Price and marginal revenue c. Price and marginal cost d. All of the above
All the tools & learning materials you need for study success - in one app.
Get started for freeThe travel-to-work time for residents of the 15 largest cities in the United States is reported in the 2003 Information Please Almanac. Suppose that a preliminary simple random sample of residents of San Francisco is used to develop a planning value of 6.25 minutes for the population standard deviation. a. If we want to estimate the population mean travel-to-work time for San Francisco residents with a margin of error of 2 minutes, what sample size should be used? Assume \(95 \%\) confidence b. If we want to estimate the population mean travel-to-work time for San Francisco residents with a margin of error of 1 minute, what sample size should be used? Assume \(95 \%\) confidence
America's young people are heavy Internet users; \(87 \%\) of Americans ages 12 to 17 are Internet users (The Cincinnati Enquirer, February 7,2006 ). MySpace was voted the most popular website by \(9 \%\) in a sample survey of Internet users in this age group. Suppose 1400 youths participated in the survey. What is the margin of error, and what is the interval estimate of the population proportion for which MySpace is the most popular website? Use a \(95 \%\) confidence level.
The average cost per night of a hotel room in New York City is \(\$ 273\) (SmartMoney, March 2009 . Assume this estimate is based on a sample of 45 hotels and that the sample standard deviation is \(\$ 65\) a. With \(95 \%\) confidence, what is the margin of error? b. What is the \(95 \%\) confidence interval estimate of the population mean? c. Two years ago the average cost of a hotel room in New York City was \(\$ 229 .\) Discuss the change in cost over the two-year period.
Consumption of alcoholic beverages by young women of drinking age has been increasing in the United Kingdom, the United States, and Europe (The Wall Street Journal, February 15,2006 ). Data (annual consumption in liters) consistent with the findings reported in The Wall Street Journal article are shown for a sample of 20 European young women. $$\begin{array}{crrrr} 266 & 82 & 199 & 174 & 97 \\ 170 & 222 & 115 & 130 & 169 \\ 164 & 102 & 113 & 171 & 0 \\ 93 & 0 & 93 & 110 & 1300 \end{array}$$ a. What is the \(95 \%\) confidence interval estimate for the mean ticket sales revenue per theater? Interpret this result. b. Using the movie ticket price of \(\$ 7.16\) per ticket, what is the estimate of the mean number of customers per theater? c. The movie was shown in 3118 theaters. Estimate the total number of customers who saw Hannah Montana: The Movie and the total box office ticket sales for the three- day weekend.
A sample survey of 54 discount brokers showed that the mean price charged for a trade of 100 shares at \(\$ 50\) per share was \(\$ 33.77\) (AAII Journal, February 2006 ). The survey is conducted annually. With the historical data available, assume a known population standard deviation of \(\$ 15\) a. Using the sample data, what is the margin of error associated with a \(95 \%\) confidence interval? b. Develop a \(95 \%\) confidence interval for the mean price charged by discount brokers for a trade of 100 shares at \(\$ 50\) per share.
What do you think about this solution?
We value your feedback to improve our textbook solutions.