00:01
Okay, so in this question, they tell us a university has 25 ,000 students, of whom 17 ,000 are undergraduates.
00:09
The housing office takes a simple random sample of 500 students, and 357 of them end up being undergraduates.
00:17
So for part a, it says, for the number of undergraduates in the sample, the observed value is blank, but the expected value is blank.
00:26
Well, they tell us that there are 357 undergraduates in the sample.
00:33
So it's given in the problem.
00:34
And our expected value is the percentage of undergraduates, which is 17 ,000 over the number of students, which is 25 ,000.
00:48
So that's going to be our percentage of undergraduates.
00:52
And our expected number of undergraduates though is that percentage times our number, our sample size basically, so 500.
01:01
So that ends up just being 68 % times 500, which is equal to 340.
01:15
So that's our expected value of undergraduates in the sample...