Alcohol-Related Fatal Car Accidents. The National Traffic Highway Safety Commiss
ID: 3160379 • Letter: A
Question
Alcohol-Related Fatal Car Accidents. The National Traffic Highway Safety Commission keeps statistics on the "mean years of potential life lost" in alcohol-related fatal automobile accidents. For males the mean years of life lost is 32. That is, on average, males involved in fatal drinking- and-driving accidents had their lives cut short by 32 years. A random sample of 36 alcohol-related fatal accidents had a mean years of life lost of 33.8, with a standard deviation of 6 years. Test whether the population mean years of life lost has changed, using a t test and level of significance alpha = 0.10. Assess the strength of the evidence against the null hypethem.Explanation / Answer
a) t=(xbar-mu)/(s/sqrt n). where xbar is sample mean, mu is population mean, s is sample standard deviation and n is sample size.
=(33.8-32)/(6/sqrt 36)
=1.8
The p value is 0.0805.
The p value is less than alpha=0.10. Reject H0 to cocnlude that population mean year sof life lost has changed.