00:01
In an experiment to measure the index of refraction in a certain material, a student repeated the experiment several times, and the results for the index of refraction are shown here.
00:12
We are asked to find the average value, the deviation in each result, and the standard deviation.
00:19
So first let's find the sample mean, the average result.
00:27
So it can be calculated as the summation of all of the values divided by the sample size.
00:39
So we'd have 1 .1 plus 1 .11 plus 1 .12 and so on, up to the last one, 1 .091.
00:52
And then we divide by the sample size, which is 9.
01:01
And this comes out to an average of approximately 1 .108.
01:08
And then we want the deviation for each result.
01:19
So that's the deviations from the mean.
01:23
So for 1 .1, it's 1 .1 minus the mean, 1 .108.
01:30
So we get minus 0 .008 approximately.
01:39
And for 1 .11 we get approximately 0 .002.
01:51
Maybe we'll go to four decimal places...