00:01
In this question, we are given in a group there are three freshmen, four sophomores, four juniors and three seniors.
00:08
So total number of students is 14.
00:15
Now, a committee of four is randomly selected.
00:18
In part a, we want to find probability the committee will consist of one student from each class.
00:24
Now, take note that these four students are selected without replacement.
00:34
And after they are selected, they are not slaughtered into any positions or titles.
00:37
So the order is not important.
00:42
So without replacement order not important, we will be using combination.
00:48
That's the one with the c.
00:50
So the committee consists of one student from each class.
00:54
So from the three freshmen, i will choose one, choose because we're using combination.
01:00
Now n probability is thumps or is plus.
01:04
So there's a thumps.
01:06
From the four sophomores, i choose one, and from the four juniors, i choose one, and from the four juniors, i choose one.
01:11
And from the three seniors, i choose one.
01:14
Now, in probability, you always divide by the total possible ways.
01:18
In this case, to choose four people without any restriction, that will be to take the 14, the total number of students, and i choose four.
01:27
And the answer is 144 out of 1001 or 0 .1439, 4 decimal place...