00:01
The sample size was given for this question which is denoted by n, this is 32.
00:05
And the mean for the sample mean that was given as 38 .7 and the standard deviation.
00:11
So this is standard deviation for um is that the sample? yeah the sample standard deviation denoted by s here that was given as 4 .5 and the confidence level which is 95 percent as a decimal number this is 0 .95.
00:24
So we have to find the confidence interval for the students spent studying for finals.
00:30
So that means we have to find the confidence interval for the population mean.
00:35
Remember the formula the sample mean plus or minus because we know the sample standard division i have to use the t distribution.
00:41
Sample standard division divided by root n.
00:44
Let me get the t value first so the alpha is 1 minus confidence level but we need alpha over 2.
00:49
1 minus 0 .95 divided by 2 which would be 0 .025.
00:53
And also i need the degrees of freedom n minus 1 which is 32 minus 1 31.
00:58
To get the t value at this step i'm going to use the graphing display calculator application inverse t...