A study was made of 413 children who were hospitalized as a result of motor vehicle crashes. Among 290 children who were not using seat belts, 50 were injured severely. Among children using seat belts, 16 were injured severely (based on data from “Morbidity Among Pediatric Motor Vehicle Crash Victims: The Effectiveness of Seat Belts,’’ by Osberg and Di Scala, American Journal of Public Health, Vol. 82, No. 3).
a) State the null hypothesis and alternative hypothesis.
b) Compute the test statistic.
c) Is there sufficient sample evidence to conclude, at the 0.05 significance level, that the rate of severe injuries is lower for children wearing seat belts?
d) Calculate the p-value.
e) State a conclusion about the null hypothesis and state a final conclusion that addresses the original claim