Question 806460

	 A consumer advocacy group wants to determine whether there is a (statistically significant) difference between the proportions of the two leading automobile models that need major repairs within 2 years of purchase.  A major repair is defined as “more than $500.”  
A sample of 500 owners of the Model A is contacted, and 80 owners indicated that their vehicles needed major repairs within 2 years.   A sample of 600 owners of Model B is contacted, and 108 owners indicated that their vehicles needed major repairs within 2 years.
Test the null hypothesis that no difference exists between the proportions in populations A and B needing major repairs against the alternative hypothesis that a difference does exist.  Use α = 0.10.