00:01
Hi, i'm david and i'm here to have you answer your question.
00:04
In the question here, we are going to discuss about the central limit theorem.
00:08
The theorem says that if the n quater equal to the 30, and then the symbol mean x -bile will be approximately to the normal, in such a way that if we take the x -bile, we minus the mean of a standard deviation, divided by square to n, we obtain the standard normal.
00:24
In the question here, we're given the fx equal to the 1 out of 3, for the x equal to the 5, 10, and the 15.
00:33
So, and equal to the 0, l square.
00:36
So the first time we need to find the mean, mule, it will equal to the e of the x, and it just equal to the sum of the x times the fx.
00:46
Then we have the 1 out of 3 time with the 5, plus 1 out of 3 times with the 10, plus 1 out of 3 times with the 15.
00:54
Then we get equal to the 10.
00:57
And we need to find the sigma square equal to the summation of the x minus the mean square temperature probability the fx so we have first volume the x equal to the 5 we minus the mean will be the 10 square 10 when the 1 of 3 the next one will be the 10 minus 10 square live 1 in 1 out of 3 plus the 15 minus the 10 square times 1 out of 3 and if we compute it, we will have 25 plus 25 divided by 3.
01:36
Will be the 50 out of 3.
01:38
Therefore we have the sigma equal to the square root of the 50 out of 3.
01:42
And then we get the answer equal to the 4 .052.
01:51
And the question asked you find the probability, now we have the n equal to the 54, is quite a 30 already...