Question

Assume that adults were randomly selected for a poll. They were asked if they​ "favor or oppose using federal tax dollars to fund medical research using stem cells obtained from human​ embryos." Of those​ polled, 484 were in​ favor, 405 were​ opposed, and 125 were unsure. A politician claims that people​ don't really understand the stem cell issue and their responses to such questions are random responses equivalent to a coin toss. Exclude the 125 subjects who said that they were​ unsure, and use a 0.05 significance level to test the claim that the proportion of subjects who respond in favor is equal to 0.5. What does the result suggest about the​ politician's claim?

Answer 1

Total number of sample (n) = 889
number of favourable events (X) = 484

We are interested in testing the hypothesis

Since, the test is two-tail test at

Decision Rule: Reject the null hypothesis if the test statistic value is less than the critical value -1.96 or greater than the critical value 1.96
The statistic value, 2.6496 is greater than the critical value 1.96. Hence, reject the null hypothesis.