00:01
Hi, i'm david and i'm here to help you asking your question.
00:03
Now let me bring up the question here.
00:06
In this question here, we are going to discuss my found with normal distribution.
00:11
Let me remind you that even the x that followed by normal, with the mean and the standard deviation, and if you tell the x will not be the mean of the standard deviation, we have kind of standard normal.
00:24
In this question here, we've given the resting heart rate x here following to normal with the mean equal to the 73 .4, standard division equals with the 5 .9.
00:38
The question i asked, let me find the percentage of the heart rate x may be greater than the at.
00:47
Now to find this probability, i need to convert the x into the z.
00:51
And she do it, i need to apply the formula here.
00:56
So if we have chitten the at, the minus the mean, divided by the standard d, and then it will compute we have the z going to be weighted than the 80 minus 73 .4 divided by the 5 .9 it will equal to the 1 .1 2 and you find this probability and if you become the z table so let me combine the z table and i'm going to put it on the right here now from the table notice that it has the negative g score when the probability on the left tail.
01:36
So right now it's not compatible with this probability yet but it will try to draw the graph on the standard normal.
01:42
It has a curve.
01:44
The middle one will be the zero.
01:46
Suppose this will be the 1 .1 .1 2.
01:49
The probability we're looking for will be the area on the right tail.
01:53
Now it will consider the one on the left on the minus 1 .1 .1 2 and the area on the left will be the same as the area on the right.
02:03
And therefore this one can write this down as a probability in the z smaller and minus 1 .1 .1 .2.
02:09
Now we can use the table and the minus 1 .1 and the 2.
02:14
The corresponding probability will equal to 0 1 .1314.
02:21
And that will be the answer for the question a...