Question

Find the standard deviation for the following set of data: 110, 145, 129, 196, 156, 133, 100, 108, 203. (Round to one more place than the data)

Answer 1

I usually use a spreadsheet for these problems..

enter all the values into your spreadsheet, with 1 value per cell.

Lets say you put them vertically into cells A1 to A9

Now you can use functions like
STDEVP( range ) to get the population std deviation
STDEVS( range) to get the sample std deviation

Or you could use the longer method.

Enter each value vertically in column A

then select the range and use the function =Average( range) to get the mean average of the data. Or you could divide the sum of all the values by their count.

Then in Column B reference each value in column A and subtract the mean average from each value.

B1 = A1 - average( range )

Then in Column C Square each result so that

Cell B1 = (A1 - Average(range))^2

Now sum all those values together

Now divide that sum by the count of the total number of values for a population std dev

or
divide the sum by the (count-1) for a sample standard deviation

then take the square root of that result and you have the standard deviation.