00:01
Hi, i'm david and i'm here to help the answer your question.
00:03
Now let me bring up your question here.
00:06
In this question here we're going to discuss about the normal distribution.
00:10
Now let me remind you that if the x that followed by the normal, with the mean and the mean and standard x minus the mean of a standard deviation, we obtain the standard normal.
00:23
In this question here we have the rainfall x will follow by the normal, in the mean equal to 18, standard division equal to the 6 intents.
00:33
Now the question i asked me to find the probability that x will be less than 10.
00:40
To find this probability, we need to convert the x here into the z.
00:46
And to do it, we apply the formula here.
00:48
So we'll turn the 10, we minus the mean of a standard deviation.
00:52
Then again equal to probability the z smaller than minus 8.
00:59
Divide in basics equal to the minus 1 .333 to find this probability i need to bring up the z table so let me combine the z table and i put it on the right here notice that the table i bring here it has the negative g score with the probability on the left tail so it is compatible with this probability with the g score equal to minus 1 .3 and 3 the corresponding probability it will equal to 0 .0 .0 .0918.
01:35
And that's going to be the answer for the a.
01:37
Now for the b, want to find the probability that x will be greater than 30.
01:42
Again, we need to convert the x into the z.
01:45
We turn the 30, we minus the mean over the standard deviation.
01:50
Then we get equal to the z greater than trial limiting by 6 equal to the 2.
01:56
Notice then this one will be the right area, which is not compatible yet...