Question

From time to time police set up roadblocks to check cars to see if the safety inspection is up to date. At one such roadblock they issued tickets for expired inspection stickers to 22 of 628 cars they stopped. Based on the results at this roadblock, they construct a 95% confidence interval for the true proportion of all drivers with expired inspections and find it to be (2%, 5%). Intepret this interval.

Answer 1

The 95% confidence interval for the proportion of drivers with expired inspections is (2%, 5%).

Step-by-step explanation:

The 95% confidence interval for the true proportion of all drivers with expired inspections is (2%, 5%).

This means that based on the results of this roadblock, we can be 95% confident that the true proportion of all drivers with expired inspections falls between 2% and 5%.

It is important to note that this interval is specific to the sample of cars that were stopped at this roadblock, and not necessarily representative of all drivers.

Answer 2

Answer: Police can be 95% confident that true population proportion lies in (2%, 5%).

Step-by-step explanation:

Interpretation of confidence interval of population proportion : A person can be 95% confident that true population proportion lies in it.

Given : From time to time police set up roadblocks to check cars to see if the safety inspection is up to date. At one such roadblock they issued tickets for expired inspection stickers to 22 of 628 cars they stopped.

95% confidence interval for the true proportion of all drivers with expired inspections = (2%, 5%).

Interpretation : Police can be 95% confident that true population proportion lies in (2%, 5%).