STATISTICS
The fx-991EX can calculate several one-variable statistics, and also analyze relationships between two data setsusing various regression models.
From the Main Menu, use the arrow keys to highlight theStatistics icon, then press p or press 6.

On the resulting menu, select 1 for “1-Variable” statistics.

A data entry screen appears.
This example uses the following list of some students’ heights,
given in inches: 70.5, 74, 67, 71, 71, 72, 73.5, 72, 69, 71.
Enter data by typing in each value one at a time, with eachfollowed by the p key.
70.5p, 74p, etc.

To calculate the 1-Variable statistics for this data set,press i3(1-Variable Calc).

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STATISTICS
13 different 1-variable statistics have been calculated, 6 of which appear on the first screen. Press R one or moretimes to reveal additional statistics:

These statistics have each been stored inside the fx-991EX as variables, in case you should wish to use them infurther calculations.
Press C to return to the data entry screen.

Enter the Option menu by pressing i.

Select item 4(Statistics Calc) to enter the Statistics
calculation area.

Press i, and then the down arrow (R) once to reveal thedifferent categories of statistical variables.

For instance, to calculate the interquartile range (IQR), press
3(Min/Max)4(Q3)-iR3(Min/Max)2(Q1)p.

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STATISTICSFREQUENCY TABLES
If the data comes from a frequency table, ClassWiz can be set up to input the data values in one column, and thefrequencies in another.
To access the set-up menu, press qp(SET UP).

Press the down arrow (R) to reach the second page and 3
to select the Statistics settings.

Press 1 to turn the Frequency option On.

The Statistics Calculation area appears again. Even thoughnothing appears to have happened, the setting has indeed
changed.

To access the Data entry area, press i3(Data).

Notice a second column for frequencies now appears andthe previous data set has been erased.

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STATISTICSEnter the same 10 students’ height used previously making
use of the Frequency column. As each data point is inputted,
ClassWiz automatically assigns a default Frequency of 1. Edit aFrequency by using the arrow keys to highlight it, then typing a
new Frequency followed by p.
Once all of the data points (x) and frequencies (Freq) have beenentered, press i3(1-Variable Calc) again to display the1-Variable statistics.

(Notice, the statistics are identical to those previously found.)REGRESSIONS
To calculate a linear regression, pressi i1(Select Type).

Select option 2(y=a+bx).

A reminder that changing the type of statistics will clear previous
data appears.
Press p to confirm and Clear memory.

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STATISTICS
Two columns for pairwise data (ordered pairs) now appears.
Note, the Frequency (Freq) column still appears; press
qp(SET UP)R3(Statistics)2(Off)to remove it.
Input the ordered pairs (1, 1), (2, 4), (3, 9), and (4, 16). Use thearrow keys to navigate to the “y” column as necessary.

To view 2-Variable statistics or the linear regression results,
press i3.

The 2-Variable statistics display calculation results for both x and y:

Press Ci4(Regression Calc) to display the linear
regression results.

Other regressions, including quadratic, logarithmic, exponential,
and geometric, can be accessed via i1(Select Type).

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fx-991EX Quick Start Guide