00:01
Okay, so in this problem, the ages of race car drivers were randomly selected, and our objective is to construct the 98 % confidence interval estimate of the age of all race car drivers.
00:12
Okay.
00:13
So the confidence interval is given by the sample mean, which is x bar plus or minus e, where e is the margin of error.
00:24
Okay.
00:25
And then the margin of error as well is given by the critical value times.
00:30
The sample standard deviation over the square root of the sample size okay where x is the sample standard deviation okay and so it means that we need to calculate the sample mean first okay so the sample mean is given by the sum of all the sample values over the sample size so when we sum all the sample values will get 504 okay and then the sample size that we have n is 15 we have 15 samples there so that will be 504 over 15 and that gives us 33 .6 okay 3 3 .6 so the next thing that we need to find is the sample standard deviation before we can calculate the margin of error okay, we need the sample standard deviation.
01:36
And so in calculating the sample standard deviation, we need the deviations from the mean.
01:44
Also, we need a square of the deviation.
01:48
Sorry, that should just be x, not x, sorry, there.
01:53
Okay, we need the square of that.
01:57
All right...