A candidate for one of Ohios two US Senate seats wishes to c

A candidate for one of Ohio\'s two U.S. Senate seats wishes to compare her support among registered voters in the northern half of the state with her support among registered voters in the southern half of the state. Based on the 95% confidence interval of (0.050, 0.112), can you reject the null hypothesis that there is no difference between the voters\' preferences between the northern and southern halves of the state?

A. no, because we do not know the P-value
B. yes, because we do not know the P-value
C. no, because the value zero is not firmly within the confidence interval
D. yes, because the value zero is not firmly within the confidence interval

Solution

D. yes, because the value zero is not firmly within the confidence interval, we can reject the null hypothesis that proportion difference is zero.