0:00
Yes, hello.
00:01
So here to set up our hypotheses, we have that our null hypothesis h0 or h sub 0 is that the proportion of voters in the district supporting the bond measure is 55%.
00:13
So p is equal to 55 % or 0 .55 versus the alternative hypothesis that the proportion of voters in the district supporting the bond measure is going to be greater than 55%.
00:29
Now we have the total sample voters in the district is 5019, the sample size 293, and the voters in the sample supporting the bond measure is 178.
00:39
So the sample proportion then, p hat, is going to be the voters supporting the bond measure is 178 out of 293, which is going to be approximately 0 .6075, so 60 .75%.
01:00
And then for the test statistic, well under the null hypothesis, we assume that p is 0 .55, so our standard error is going to be equal to p times the square root of p times 1 minus p over n.
01:13
So that's the square root of 0 .55 times 1 minus that, so times 0 .45 over n, so over 293, that's under the square root.
01:24
And then our z score is going to be p hat minus p over the standard error.
01:33
So we find our z score then as p hat minus p over the standard error.
01:40
And since we have a one -tailed test, we're only interested if the proportion is greater than 55%...