A carpet cleaning company is doing some research to determine if its rates are lower than those of its competitors. A researcher posed as a householder to get prices for cleaning a bedroom carpet. The average of 15 such prices was $87.43, with a standard deviation of $16.23. Is this average significantly higher than the company's own price of $85 for such a job? You may assume that the population data are normally distributed. What should the company do? Use α = 0.05.
Answer to relevant QuestionsA drug company has developed a new formulation of a popular pain reliever. It appears that the new formula provides quicker pain relief than the old formula, which provided relief in 15 minutes, on average. The company wants ...An online poll conducted by Ipsos Reid on behalf of Rogers Wireless in May 2009 concluded that "two in ten (17%) of cellphone and smartphone users typically access the Internet on a daily basis from their phone."3 Although ...As a student, you are suspicious that some teachers give easier tests than others. You have heard that Mr. Wilson is one such teacher, and you are thinking of switching to his class. However, you want to be sure that Mr. ...The survey of drugstore customers also collected data on ages. Lynda Parks has always thought that the average age of her customers is around 40. At the 5% level of significance, what can you conclude, based on the sample ...The college cafeteria manager claims that 90% of cafeteria customers are satisfied with the range of food served and prices. Suppose that in a random sample of 500 cafeteria customers, 438 say they are satisfied with the ...
Post your question