00:01
Hello, students.
00:02
We are going to write here a class of 19 students.
00:05
Four are both measures.
00:06
A group of four students are chosen.
00:10
So we are going to write here for this.
00:12
In the first case, what is the probability that group has no math measures? so this is probability we are going to write here for this.
00:22
So 19 students.
00:23
So total students which has no math measures.
00:28
We are going to write here for this.
00:31
These are, so let's erase this to make it more clear.
00:37
If i write here for this, this is 19 minus 4, that is 15.
00:44
So basically if i write here for this, this is 15c4, probable outcomes divided by total outcomes, which is 19c4.
00:54
So basically if i write here for this, this must be equivalent to, so if i calculate by using our calculator, this is 1365 divided by 3876, that must be equivalent to 0 .3522.
01:14
And if i write here, this is going to be our final probability in the first case.
01:20
Now let us talk about our b part probability.
01:25
So let's erase this to make it more...