00:01
It's given here that a university has twice as many undergraduate students as graduate students.
00:08
That means that for a randomly selected student, the probability that they are an undergrad, let's call that u, is equal to twice the probability that they are a graduate student.
00:20
Let's call that g.
00:24
Also, you can only be an undergraduate student or a graduate student.
00:28
There are no other categories.
00:30
So we have the probability of u plus the probability of g must equal 1.
00:40
If we take these two equations, we get 2 times the probability of g plus the probability of g equals 1.
00:53
That's substituting 2 times the probability of g for the probability of u in the second equation.
01:00
And so that means that the probability of g is 1 over 3, and therefore the probability of u is 2 over 3.
01:14
Now it's also given that of the graduate students 25 % live on campus.
01:21
So that is a conditional probability that says the probability of living on campus, let's call that c given that your graduate student, is 0 .25.
01:38
And it's also given that 10 % of undergraduate students live on campus.
01:44
So that means the probability of living on campus given you is 0 .1 now for question one, we're asked if a student is chosen at random, what is the probability that the student is an old student living on campus? i'm assuming what they mean by old is graduate.
02:08
And for the second question, new means undergraduate.
02:11
That's my assumption...