00:01
Hello, let's have a look on the question.
00:02
So it is given to us that we have a four -sided dice having 1, 2, 3 and 4 written on it.
00:08
So from here we can say that probability of 1, 2, 3 and 4 coming up will be equal to 1 upon 4.
00:14
So for the a part, we need to find out that he will stop after exactly 3 throats.
00:29
So in this case, the probability will be equal to since he is stopping after 3 throats.
00:34
So first he will get 4, that is 1 upon 4.
00:37
Multiplyed by again 1 upon 4 because he is stopping at the third throw.
00:43
So for third throw, he can get 1 upon 4.
00:46
He can get 1 that is 1 upon 4, he can get 2 that is revivarity 1 upon 4 or he can get 3 that is 1 upon 4.
00:54
Or he can get 3 that is 1 upon 4 because all 3 have 1 upon 4 vibranity.
00:59
So from here we can write this is 1 upon 16 multiplied by 3 divided by 4.
01:04
That is 64 by, this is 3 by 64.
01:09
So this will be equal to 0 .0469.
01:12
This is the required probability.
01:14
Next we need to find out the expected value.
01:17
So x here is following geometric distribution with probability is equal to 3 by 4.
01:24
And expectation of, expectation of geometric is given by q divided by p.
01:33
So q here will be equal to 1 minus p, that is 1 .4, divided by 3 upon 4.
01:39
So this will be equal to 1 upon 3.
01:42
This is the expected value.
01:43
The 3 part, he will get $1 .5...