20 out of the 50, which is the same thing, is 0.4, and then she wants to construct a 99% confidence interval. So before we even go about constructing the confidence interval, you wanna check to make sure that we're making some valid assumptions, we're using a valid technique. So before we actually calculate the confidence interval, let's just make sure that our sampling distribution is not distorted in some way, and so that we can, with confidence, make a confidence interval. So the first condition is to make sure that your sample is truly random, and they tell us that it's a simple random sample, so we'll take their word for it. The next condition is to assume that your sampling distribution of the sample proportions is approximately normal, and there, you wanna be confident, or you wanna see that in your sample, you have at least 10 successes and at least 10 failures. Well, here, we have 20 successes, which means, well, 50 minus 20, we have 30 failures. So both of those are more than 10, and so meets that condition.