00:01
Part a is false.
00:02
We are not given enough information to disregard whether this is a normal or not a normal distribution, but we have a sample size of 64 patients, and the distribution between 128 and 147 is not very spread.
00:18
It's not very skewed.
00:19
So we can assume this is at least slightly a normal distribution.
00:23
So option a is false.
00:26
Option b says we are 95 % confident that the average waiting time for this 64 emergency room patients is between 128 and 147 minutes.
00:37
This is not true because the confidence interval is not for the estimate.
00:42
So the 64 patients, that's the observation and that's the point estimate is called.
00:50
And it's not.
00:51
The confidence interval is for the general estimation.
00:55
Is for the population parameter.
00:58
It's not for the point estimate.
00:59
So option b is also false.
01:04
Option c is true because this is the definition of the confidence, of the 95 % confidence interval.
01:11
Because it's about the average waiting time of all the patients in the hospital, not just of the sample.
01:19
So yes, option c is true.
01:23
Option d says that a 95 % sorry, 99 % confidence interval will be narrower than the 95 % confidence interval...