00:01
The sample size for this question denoted by n, that was given as 37, and the sample mean denoted by x bar, which is 194 .6, and the population standard division 55 .6, and the confidence level, which is given as 95 % as a decimal number, we can write as 0 .95.
00:19
So we have to calculate the confidence interval for the population mean.
00:23
Let's remember the formula, the confidence interval for the population mean, which is the sample mean, plus or minus, because we are given the population standard division, so we have to use the z distribution times population standard division divided by root n.
00:36
Let's get the z value first.
00:38
So the alpha is 1 minus confidence level, but i need alpha over 2, 1 minus 0 .95 and divide by 2, which would be 0 .025.
00:47
To get the z value, so i'm going to use the graphing display calculator application, inverse norm, and the area, so the mean and the standard division for the standard distribution, plus second variance and the inverse norm, 0 .025, and the mean and the standard division.
01:02
So the value is 1 .96...