 Welcome. We're now going to use technology to build a confidence interval for a population proportion. If my sample size n is 160, my sample proportion p hat is 0.26. Construct a 99% confidence interval. Give your answer to three decimals. So they're pretty nice to us. They directly gave us our sample size in 160. They gave us our sample proportion of 0.26. Then they gave me my confidence level of 99% or 0.99. In our Google Sheets, the only other piece of information we're going to need is X. Number of successes here. X is always going to be n times p hat. n times p hat. So out of 160 of something, there were 0.26 or 26% that possessed a certain characteristic. 160 times 0.26 is going to give you 41.6. And you can round this to 42, but to keep your answer as accurate as possible, we're going to leave it as 41.6. So my goal is going to build a confidence interval predicting the true population proportion p. I'll have a left bound. I'll have a right bound. Let's go to Google Sheets. In Google Sheets, you'll go to the data list tab. And then you'll go to the one proportion confidence level region, columns D and E. My X in this case will be 41.6. My sample size n is 160. The only other piece of information you need is a confidence level of 0.99. And it turns out that in this specific instance, my confidence lower limit is going to be 0.171. And my upper limit will be 0.349. 0.171, 0.349. So what this is telling me that the true population proportion will be somewhere between 0.171 and 0.349. And that's with 99% confidence. Another way to write a confidence interval would be to use parentheses, 0.171 on the left, 0.349 on the right. This is the interval notation form. So first I did inequality notation, then you can also do interval notation as well. Both are perfectly acceptable answers. Well once again, I hope you enjoyed. Thanks for watching.