00:01
Hi there.
00:02
In your question, we're looking at a couple different things here.
00:06
So i'm going to bring out into steps and see if that can help at all.
00:10
So the confidence interval i'm calling ci is given as x bar plus or minus z star times sigma over the square root of n.
00:28
This is the general formula.
00:30
And now we're not really too concerned about x bar or the average.
00:35
That doesn't really come into play here in this question at all.
00:38
So in part one, we are told, i'll do this part in blue, that we have 50 patients, so we'll call that n, we're told it's the 95 % confidence interval, and we are told that we have plus or minus 0 .5.
01:00
So what this tells us now is we'll have 0 .5 is equal to z star sigma square root n.
01:10
Sigma is the unknown.
01:13
We're going to go ahead and solve for that...