Before 1918, approximately 55% of the wolves in the New Mexico and Arizona region were male, and 45% were female. However, cattle ranchers in this area have made a determined effort to exterminate wolves. From 1918 to the present, approximately 65% of wolves in the region are male, and 35% are female. Biologists suspect that male wolves are more likely than females to return to an area where the population has been greatly reduced. (Round your answers to three decimal places.) (a) Before 1918, in a random sample of 11 wolves spotted in the region, what is the probability that 8 or more were male?What is the probability that 8 or more were female?What is the probability that fewer than 5 were female?(b) For the period from 1918 to the present, in a random sample of 11 wolves spotted in the region, what is the probability that 8 or more were male?What is the probability that 8 or more were female?What is the probability that fewer than 5 were female?

An fruit grower knows from previous experience and careful data analysis that if the fruit on a specific kind of tree is harvested at this time of year, each tree will yield, on average, 127 pounds, and will sell for $4.6 per pound. However, for each additional week the harvest is delayed (up to a point), the yield per tree will increase by 2.1 pounds, while the price per pound will decrease by $0.07.   A) How many weeks should the grower wait before harvesting the apples in order to maximize the sales revenue per tree? (Round your answer to the nearest tenth of a week.)   Answer: __________ (rounded to the nearest tenth)   B) Use your answer in part A to find the actual maximum revenue that can be expected. (Round your answer to the nearest dollar.)   Answer: ____________ dollars (rounded to the nearest dollar)

In a certain year, it was estimated that 1,000,000 of the 307,000,000 residents of the United States are HIV-positive. (HIV is the virus that is believed to cause AIDS.) The Repeatedly Reactive Immunoassay (RRIA) diagnostic test correctly diagnoses the presence of AIDS/HIV 99.7% of the time and correctly diagnoses its absence 98.5% of the time. (Round your answers to four decimal places.) (a) Find the probability that a person whose test results are positive actually has HIV.(b) Find the probability that a person whose test results are negative does not have HIV.(c) Find the probability that a person whose test results are positive does not have HIV.(d) Find the probability that a person whose test results are negative actually has HIV.(e) Which of the probabilities would you be interested in if you or someone close to you tested positive? the probability that a person whose test results are positive actually has HIVthe probability that a person whose test results are negative does not…

.    In 2010, of a total of 67,000 rooms on the Las Vegas Strip, Caesars Entertainment managed 22,880, while MGM Resorts managed over 12,000. However, owing to the Great Recession and new hotel openings, between 2008 and 2010, MGM's hotel occupancy decreased from 92% to 89%, while its average daily room rate fell from $148 to $108. Meanwhile, CityCenter, managed by MGM Resorts, and the Cosmopolitan opened with 4,000 and 3,000 rooms respectively, and the 1,720-room Sahara closed.  (Sources: Caesars Entertainment Corp., Annual Report 2010; MGM Resorts, Annual Report 2010; "Sahara's closure on May 16 will mark `the end of an era'," Las Vegas Sun, March 11, 2011.) (a) Using a suitable figure, explain how the opening of CityCenter and the Cosmopolitan affects the residual demand for an existing hotel and how it should adjust prices. (b) If MGM Resorts had not reduced its room rates, what would have been the effect on occupancy? (c) Use the Cournot model to explain…

2. Rini prefers red M&Ms over any other color. The Mars Company, makers of M&Ms, claims that 20% of all M&Ms are red. Rini plans to remove M&Ms from her bag one at a time until she gets her first red. How many M&Ms should she expect to remove?

Step 3: Assess the Evidence (Calculate the test statistic for the observed sample mean. Sketch the T-distribution and identify the position of the observed test statistic. Shade the area that represents the P-value. Use the test statistic to find the P-value.)

How would you answer this?

An analyst in the real estate business is interested in the relationship between the cost of the monthly rent of an apartment and the size of an apartment, in big cities.  She gathers data for apartment buildings in 12 cities in 12 different states.  In each city, she gets the numbers for at least 5 different buildings and at least 40 apartments in each building.  She reaches the following conclusion: the rental cost of a 2-bedroom apartment is 50% more than the rental cost of a 1-bedroom apartment, and the rental cost of a 3-bedroom apartment is 50% more than the rental cost of a 2-bedroom apartment. Based on the paragraph, what is the minimum number of apartments she collected data on? Do you think her sample was large enough to be statistically valid? Based on the paragraph, are there any apartments or apartment buildings that she would have excluded from her study? Do you see any bias in how she selected apartments for her study? Based on the paragraph, is there a positive…

5 Imagine that a company sells portable walkie-talkie radios to construction crews. The batteries for these radios last for an average of 55 hours. The purchasing manager for this company receives a brochure in the mail that advertises a new brand of batteries. This new brand of batteries is cheaper than the brand that the company currently uses. However, the purchasing manager is concerned that the cheaper batteries may have a shorter average battery life than the current brand. (Note: The number of hours that batteries last is called their battery life.) The pricing manager installs 40 randomly selected batteries of the cheaper brand in the company's walkie-talkie radios. He finds that the mean battery life for the sample is 52 hours, with a standard deviation of 10 hours. He wants to perform a statistical test at the 1% level of significance to determine whether the cheaper batteries have a shorter average battery life span than the average life span of the brand of batteries the…

A media personality argues that global temperatures are not rising, because every year an increase is reported, such as 0.09 degrees C. The difference from the previous year is less than the margin of error of about 0.13 degrees C, so that difference should be ignored. What is a strong counter argument?   The difference is only 0.4 but that is still a significant change.   The change of 0.9 is not a lot and thus should be ignored.   The margin of error is larger than the increase so we should consider it an issue just extra information and thus can be ignored.   The margin of error is quite small compared to the change year over year, so it is a significant issue.