Car Accidents Among Young Drivers. Use the following information for Exercises 45–47. The National Transportation Safety Board publishes statistics on the number of automobile crashes that people in various age groups have. Young people ages 18–24 have an accident rate of 12%, meaning that on average 12 out of every 100 young drivers per year had an accident. A researcher claims that the population proportion of young drivers having accidents is greater than 12%. Her study examined 1000 young drivers ages 19–24 and found that 134 had an accident this year.
45. Perform the appropriate hypothesis test with level of significance .
9.5.45
Both and , so the conditions for using the test for proportions are met.
Step 1 We reject if the .
Step 2
Step 3
Step 4 The is not , so we do not reject . There is insufficient evidence at level of significance that the population proportion of young people ages 18–24 who have had an accident has increased from 12%.