Question

According to the Insurance Institute for Highway Safety, the national rate for 16-year-old males was 210 accidents for every 1000 drivers (21%) during the year 2000. In a large city in the Midwest, a random sample of 150 16-year-old male drivers found that 25 of them had been in an accident during the year 2000. Does this city have a lower proportion of accidents by 16-year-old male drivers than the national proportion?

Answer 1

Yes. The city has a lower proportion of accidents by 16-year-old male drivers than the national proportion (16.7% compared to 21%).

Explanation:

a) Data and Calculations:

Number of 16-year-old males involved in driver accident during year 2000 = 210

Sample number of drivers = 1,000

National rate of accidents for 16-year-old males for every 1,000 drivers = 21% (210/1,000 * 100)

Random sample of 16-year-old male drivers in a Midwest city = 150

Number of them involved in driver-accidents = 25

Proportion of 16-year-old males involved in driver-accidents = 25/150 * 100 = 16.7%

The city's 16.7% proportion is lower than the national proportion of 21%.