00:01
Hi, i'm david and i'm here to help you answer your question.
00:03
In the question here we are going to discuss about the normal distribution.
00:07
Let me remind you that if we have the x that follows by the normal with the mean and the standard deviation, if we turn the x minus the mean of standard deviation, we obtain the standard normal.
00:18
In the question here we have the x that follows by the normal when the mean equal to the 1 ,9002, standard deviation equal to the 587.
00:30
And if you answer most of the questions correctly, so we'll chop on your work down.
00:35
And then here i will answer the question d and e for you.
00:40
In the question d, i have to find the probability that the x will be between the 200, 2028 and the 2148.
00:54
To find this probability, i need to convert the x into the z.
00:57
To do it, i need to apply this formula here.
01:00
And then i will have equal to the 2028 we minus the mean divided by the standard deviation and then on the right we will have minus 1902 over the 587 and if we compute we have the z will be between the 2028 minus 1902 divided by the 587 can equal to the 0 .2 the 0 .2 and have 2148 minus 190 2 divided by the 57 can equal to the 0 .419.
01:42
This one can be written down as a probability that z is smaller than the 0 .419, minus probability the z is smaller than 7215...