Question

During an orientation event at a large university, incoming students are advised about the cost of textbooks for a typical study period. A sample of 100 students currently enrolled at this university indicates a sample mean cost of $315.40. A population standard deviation is known to be $43.20. (a) (8 marks) Construct a 95% confidence interval for the true population mean cost of textbooks. Explain what the values you have calculated mean. Provide a diagram (a template is available on the course website) to assist in your explanation. (b) (3 marks) Does the population cost of textbooks have to be normally distributed here? Explain briefly (c) (5 marks) Suppose that the campus newspaper previously claimed that the average cost of textbooks was $300 per study period. If the campus newspaper's claim were still true, what would be the probability, in a sample of 100 students, of a mean cost of textbooks above $310?

Answer 1

Here e have ว่า 100 ' 315.40 and 6 43.20 At 의5% confidence Love evel wi be calcutated by 4-3. 2O NIOO