00:01
We have a clinic where there are 15 patients and four of the patients have the flu.
00:08
And we're asked if we were to randomly select three patients, what is the probability that all three have the flu? so if all three have the flu, that means the first one has to have the flu, and the second one has to have the flu, and the third has to have the flu.
00:39
For the first patient, the first selected patient, the probability of that one having the flu is the number that have the flu divided by the total number of patients.
00:51
That's 4 out of 15.
00:54
And then for the second, it's the number of patients who have the flu, so there's only three of those left, divided by the total number of remaining patients.
01:04
That's 14.
01:06
And for the second patient, the probability, or the third patient, the probability of that one having the flu is 2, that's the total number who have the flu that haven't been selected yet, divided by the total number remaining...