00:01
Okay, so i see that you need help with this question, and it has four test scores of 22, 99, 102, 33, 57, 75, 100, 81, 62, and 29, and it wants you to calculate the standard deviation of the data by hand.
00:21
Use a chart below to record your steps.
00:23
So you did not provide the chart, which is fine.
00:26
So i'm just going to list out your numbers, 102, 33, 57, 75, 100, 81, 62, and 29.
00:40
First thing i have to do is i have to add up all the values, so the sum is 660.
00:46
I'm going to divide by 10, and so your mean is 66.
00:51
So then i'm going to subtract each value from your mean, and then square it.
00:58
So i'm just going to write this down, minus 66 squared, minus 66, and then square it, minus 66, and then square it, minus 66, and then square it, minus 66, and then square it, minus 66, and then square it, minus 66, and then square it.
01:20
So 22 minus 66, and then squaring that is 1936, then 99 minus 66, and then squaring that is 1089.
01:39
102 minus 66 is 36, squaring that is 1296...