00:01
We're going to be creating a 99 % confidence interval for the proportion of those who picked category a.
00:11
And for this, we have our sample proportion, which is 0 .18 or 18%.
00:19
And our sample size is 425.
00:23
Now, from the 99 % confidence interval, if we look it up in a z table, we can find out that our critical value at z is going to equal 2 .576.
00:37
And from our population, sorry, not from our population, from our sample proportion, we can find out that the complement of that, which is q -hat, is going to equal 0 .8.
00:50
You just take 1 and you subtract 0 .18 to get 0 .82.
00:57
So from there, we need to figure out our point estimate.
01:01
Now our point estimate for this type of problem is just going to be the same thing as our population.
01:10
I keep saying population.
01:11
I mean sample.
01:12
Sample proportion.
01:14
We're going to be estimating the population proportion using our samples...