00:01
Hello students, let's solve this problem.
00:02
The problem says a set of 1 -2 -0 exam scores is normally distributed with mean is equal to 74 and sb is equal to 8.
00:28
So the first question is given, how many students score higher than 74? that is the first question is given.
00:44
So mean is given, standard deviation is given.
00:48
So we have to find out e of x, that is of 74, tilda is equal to 8, and this one is equal to square is 64.
01:03
Now, x minus ex divided by root under var x.
01:16
So that is of n 0 .1.
01:23
So x minus 74 divided by root of 64.
01:31
So x minus 74 divided by 8 that is of n 0.
01:40
Of 1.
01:42
We have to find out p of x greater than 74.
01:48
So that means p x greater than 74 divided by 8.
01:57
So greater than 74 minus 74 divided by 8.
02:03
So that p of z greater than 0.
02:08
So 1 minus p of z less than equal to 0.
02:15
So then p of z less than equal to 0 means 1 minus 1 by 2...