Question

1. You want to determine the percentage of seniors who drive to campus. You take a random sample of 125 seniors and ask them if they drive to campus. Your 95% confidence interval turns out to be from 0.69 to 0.85. Select each correct interpretation of this situation. There might be no, one, or more than one correct statement. Explain, the reason if it is not a correct interpretation.

1. 77% of the seniors in your sample drive to campus.

2. 95% of all seniors drive to campus from 69% to 85% of the time, and the rest drive more frequently or less frequently.

3. If the sampling were repeated many times, you would expect 95% of the resulting samples to have a sample proportion that falls in the interval from 0.69 to 0.85.

4. If the sampling were repeated many times, you would expect 95% of the resulting confidence intervals to contain the proportion of all seniors who drive to campus.

5. You are 95% confident that the proportion of seniors in the sample who drive to campus is between 0.69 and 0.85.

6. You are 95% confident that the proportion of all seniors who drive to campus is in the interval from 0.69 to 0.85.

7. All seniors drive to campus an average of 77% of the time.

8. A 90% confidence interval would be narrower than the interval given.

Answer 1