Exhibit 18-5
Forty-one individuals from a sample of 60 indicated they oppose legalized abortion. We are interested in determining whether or not there is a significant difference between the proportions of opponents and proponents of legalized abortion.
-Refer to Exhibit 18-5. The conclusion is that there
A)is no significant difference between the proportions
B)is a significant difference between the proportions
C)could be a difference in proportions, depending on the sample size
D)None of these alternatives is correct.

Question

Quizplus · Accepted Answer

The sample proportion of opponents of legalized abortion is 41/60, or approximately 0.683. We can use a hypothesis test for the difference in proportions to determine whether this proportion is significantly different from 0.5 (assuming equal proportions of opponents and proponents). The test statistic for this hypothesis test is (0.683 - 0.5) / sqrt[0.5 * 0.5 * (1/60 + 1/60)], which is approximately 2.353. Looking at a standard normal distribution table, we can see that the probability of getting a test statistic this extreme or more extreme is less than 0.05. Therefore, we reject the null hypothesis and conclude that there is a significant difference between the proportions of opponents and proponents of legalized abortion.

Exhibit 18-5 Forty-One Individuals from a Sample of 60 Indicated They Oppose