00:05
So here's the information that we're given about our sample size, the probability of success.
00:11
Then our probability of failure would be one minus that.
00:14
And then we're told p hat is equal to .4476.
00:20
So first i'm going to calculate the mean.
00:22
This one's pretty easy because the mean for using a normal approximation would simply be p hat.
00:31
And then the standard deviation would be 0 .05 times 0 .9.
00:39
Divided by 134.
00:43
So opening up my calculator, 0 .05 times 0 .95 divided by the sample size.
00:59
And there's our standard deviation.
01:08
Approximately 0 .0188.
01:12
So if we go five places, 1, 2, 3 .3.
01:17
Now to calculate the probability that p hat is less than this particular value, i'm going to change this to a z score...