00:01
We want to find out if this telemarketer was misled.
00:05
He was told that 15 % of the calls should end up in sales.
00:09
He did 150 calls and only 20 more sales.
00:13
We are going to run a one -prop -z test to see if we can say he's got enough to think he was misled.
00:20
First thing we've got to do is check conditions.
00:23
We are going to assume that these are a simple random sample of his calls.
00:28
They are independent because one call does not.
00:30
Affect the other and 150 calls is less than 10 % of all calls made so we can say it's less than 10 % of the population because all those are met we can use the one prop c test in order to do that we have to set up our null and alternative hypothesis our null hypothesis is that the sample that we got is actually equal to the sample proportion our alternative is we think that the proportion portion is actually less than what we were told.
01:07
So in order to find out what p hat is, we're going to go through and take 20 and divide it by 150, and that gives us a value of 0 .13.
01:20
3 is continuing.
01:22
So he sold 13 % of his calls.
01:26
To find the standard deviation, we are going to do p1 minus p divided by n...