10 questions

23 minutes

See All test questions

1. Suppose that the regression line for a set of data, = mx + 3, passes through the point (2, 7). If and are the sample means of the x- and y-values, respectively, then =

2. A study is made to determine whether more hours of academic studying leads to higher point scoring by basketball players. In surveying 50 basketball players, it is noted that the 25 who claim to study the most hours have a higher point average than the 25 who study less. Based on this study, the coach begins requiring the players to spend more time studying. Which of the following is a correct statement?

3. The longevity of people living in a certain locality has a standard deviation of 14 years. What is the mean longevity if 30% of the people live longer than 75 years? Assume a normal distribution for life spans.

4. Which of the following is a correct statement about correlation?

5. Which of the following are affected by outliers?

I.Mean

II.Median

III.Standard deviation

IV.Range

V.Interquartile range

6. An engineer wishes to determine the quantity of heat being generated by a particular electronic component. She knows that the standard deviation is 2.4 and wants to be 99% sure of knowing the mean quantity to within ±0.6. Which of the following should be used to find the sample size (n) needed?

7. A company that produces facial tissues continually monitors tissue strength. If the mean strength from sample data drops below a specified level, the production process is halted and the machinery inspected. Which of the following would result from a Type I error?

8. Two possible wordings for a questionnaire on a proposed school budget increase are as follows:

I.This school district has one of the highest per student expenditure rates in the state. This has resulted in low failure rates, high standardized test scores, and most students going on to good colleges and universities. Do you support the proposed school budget increase?

II.This school district has one of the highest per student expenditure rates in the state. This has resulted in high property taxes, with many people on fixed incomes having to give up their homes because they cannot pay the school tax. Do you support the proposed school budget increase?

One of these questions showed that 58% of the population favor the proposed school budget increase, while the other question showed that only 13% of the population support the proposed increase. Which produced which result and why?

9. Suppose that for a certain Caribbean island in any 3-year period the probability of a major hurricane is 0.25, the probability of water damage is 0.44, and the probability of both a hurricane and water damage is 0.22. What is the probability of water damage given that there is a hurricane?

10. A union spokesperson is trying to encourage a college faculty to join the union. She would like to argue that faculty salaries are not truly based on years of service as most faculty believe. She gathers data and notes the following scatterplot of salary versus years of service.

Which of the following most correctly interprets the overall scatterplot?