Correcting Accumulated Statistics; Mean - HP 12C Platinum User Manual

94 Section 6: Statistics Functions
The table below shows where the accumulated statistics are stored.
Register
R (and display)
1
R
2
R
3
R
4
R
5
R
6

Correcting Accumulated Statistics

If you discover you have entered data incorrectly, the accumulated statistics can
easily be corrected. Simply key in the incorrect data point or data pair again as if
it were new, but press g^ instead of _. Then enter the correct data point or
data pair and press _.

Mean

Pressing gÖ calculates the means (arithmetic averages) of the x-values (
y
of the y-values ( ). The mean of the x-values appears in the display after gÖ is
pressed; to display the mean of the y-values, press ~.
Example: A survey of seven salespersons in your company reveals that they work
the following hours a week and sell the following dollar volumes each month. How
many hours does the average salesperson work each week ? How much does the
average salesperson sell each month ?
n: number of data pairs accumulated.
Σx: summation of x-values.
: summation of squares of x-values.
Σx 2
Σy: summation of y-values.
summation of squares of y-values.
Σy 2
Σxy: summation of products of x-values and y-values.
Statistic
x
) and