00:01
In this question, we are looking at a normal distribution, so let's start by drawing it.
00:06
The total area under this curve is 1, or 100%, and it is symmetric.
00:11
Its mean is 94 minutes, its standard deviation is 5 minutes.
00:17
And in part , we want the probability a randomly selected match lasts longer than 100 minutes.
00:24
So x, an observation from this curve, is greater than 100.
00:28
That's above the mean, so let's mark it down here.
00:31
Greater than means we're looking at the area to the right.
00:35
Now to find this area you need something with the normal distribution built into it.
00:39
The function you would have to integrate is just too complicated.
00:43
You could use software like excel.
00:45
I'm going to use my ti -84 calculator with the normal cdf function.
00:51
It has four inputs, outputs, lower bounds, upper bounds, mean, and standard deviation...