Question about Texas Instruments TI-30XA Calculator

# Mean (x-bar), variance (s^2) and standard deviation (s)

I see that there is an x-bar function, but I don't know how to input the numbers. I've tried to add all the numbers together, eg:
1+2+3+4+5 then i type = and i get 14. And then I pressed 2nd [x-bar]. But it says error.
How do I do it ?!?

Also, is it possible to find the variance or standard deviation of the numbers that I've found x-bar for??

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Enter 1 then press the (SIGMA)+ button (SIGMA) looks like a sideways capital M ....its a Greek letter.

Then enter 2 and press the (SIGMA)+ button
Then enter the next value and press the (SIGMA)+ button

After you press the (SIGMA)+ button the calculator displays the number of numbers you have entered

Once all numbers of your sample have been entered press 2nd and the button corresponding to x-bar

sample st. dev is the (sigma)n-1 button (need to use 2nd button)
variance is (std. dev.)^2

population st. dev is the (sigma)n-1 button (need to use 2nd button)
variance is (std. dev.)^2

Posted on Mar 12, 2008

• hannah0205 Jan 24, 2011

Thank you so much MathTim. You had make a different :) I am so glad that I able to use my cal to find standard deviation and variance.

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(8 - 12 xbar) 2

Posted on Mar 15, 2010

Hi there,
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Posted on Jan 02, 2017

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## Related Questions:

### 2nd vars 2 (normalcdf( -999999,-.1923) Just trying to get area from z value -.0.1923 keep getting errors

The normalcdf function takes three arguments: the z value, the mean, and the standard deviation. In the "standard" case the mean is 0 and the standard deviation is 1. Thus, try calculating
normalcdf(-.1923, 0, 1) .

Jun 29, 2011 | Texas Instruments TI-84 Plus Silver...

### How to solve mean, variance and standard deviation on the ti 83

get the TI 84 for dummies book, and check the statistic functions - they are fantastic - got me an A in statistics - once you start using them, you must practice- a function for everything!!

Jan 29, 2011 | Texas Instruments TI-83 Plus Calculator

### How to solye statistics problem

I have no clear idea what you mean by solve statistics problem. But if your problems involve finding the standard deviation and other statistical values then this post will help you.

The variance is the square of the standard variation

TO COMPUTE STANDARD DEVIATION AND 2-VAR STATISTICS.

I assume you know the theory. I will show you the key strokes

for 1-Var statistics
Press [MODE][3:STAT] [1:1-VAR]. You are ready to enter values in the X column.
Enter a number and press [=]. Cursor jumps to second number to enter.
Keep entering numbers and pressing [=] till all numbers are in. Press the [=] key after the last one.
Press [AC] key to clear the screen.
Press [SHIFT] [STAT] (above digit 1.) then [5:Var]. Screen displays the statistical variables 1:n ;2: x bar; 3: x sigma n; 4:x sigma n-1.
Press the number corresponding to the statistical value you want, ex 1:n . The variable appears on screen. Press [=] and it will be displayed.
To display another variable press [SHIFT][STAT][5:Var][ 1,2, 3, or 4] .

To access the sum of squares sigma x^2 and the sum of data sigma x press[SHIFT][STAT][4:SUM] then [1: for sigma x^2] or [2: for sigma x]. Press [SHIFT][STAT][6:MinMax] to access minX and maxX.

For 2-var statistics
To perform 2 variable statistics you press [MODE][3:STAT] and any of the other regression options (except 1:1-Var). A two column template opens where you enter the X and Y values. When finished entering data, press [SHIFT][STAT][5:Var]. to access the different statistics. As I assumed above, you should be able to recognize what each variable means.

Dec 22, 2010 | Casio FX-115ES Scientific Calculator

### How do I get the variance, the standard deviation, and the sample standard deviation in a casio FX-115Es.. Thank you

The variance is the square of the standard variation

TO COMPUTE STANDARD DEVIATION AND 2-VAR STATISTICS.

I assume you know the theory. I will show you the key strokes

for 1-Var statistics
Press [MODE][3:STAT] [1:1-VAR]. You are ready to enter values in the X column.
Enter a number and press [=]. Cursor jumps to second number to enter.
Keep entering numbers and pressing [=] till all numbers are in. Press the [=] key after the last one.
Press [AC] key to clear the screen.
Press [SHIFT] [STAT] (above digit 1.) then [5:Var]. Screen displays the statistical variables 1:n ;2: x bar; 3: x sigma n; 4:x sigma n-1.
Press the number corresponding to the statistical value you want, ex 1:n . The variable appears on screen. Press [=] and it will be displayed.
To display another variable press [SHIFT][STAT][5:Var][ 1,2, 3, or 4] .

To access the sum of squares sigma x^2 and the sum of data sigma x press[SHIFT][STAT][4:SUM] then [1: for sigma x^2] or [2: for sigma x]. Press [SHIFT][STAT][6:MinMax] to access minX and maxX.

For 2-var statistics
To perform 2 variable statistics you press [MODE][3:STAT] and any of the other regression options (except 1:1-Var). A two column template opens where you enter the X and Y values. When finished entering data, press [SHIFT][STAT][5:Var]. to access the different statistics. As I assumed above, you should be able to recognize what each variable means.

Oct 27, 2010 | Casio FX-115ES Scientific Calculator

### Hello. I just wanted to ask you how do I calculate the variance and standard deviation in my cfx9850GB plus. I had a quick look at the manual but I couldnt find the info. thankz .

This shows you how to enter your data and calculate some statistical values. Keep in mind that the variance is the square of the standard deviation.

In the main menu select [STAT] icon to enter Stat mode and display the statistical data lists. Use the statistical data lists to input data and perform statistical calculations. Use the arrows to move the highlighting around the lists.
Example: Enter the following values in List 1
1st line enter 90 [EXE]
2nd line 85 [EXE]
3 79 [EXE]
4 75 [EXE]
5 70 [EXE]
6 68 [EXE]
7 56 [EXE]

When finished you press [F2:Calc], then [F1:1Var] and the statistical results appear on screen.

Title of screen : 1-Variable
x bar =74.7142857
Capital Sigma x= 523
Capita Sigma X squared = 39851
x lower case sigma n = 10.5249945
x lower case sigma n-1= 11.3682934
n = 7
Scroll down with Down arrow to access other data
minX =56
Q1=68
Med =75
Q3=85
Xbar -x lower case sigma n =64.1892911
x bar x lower case sigma n = 85.2392802
maxX=90
Mod=90

All you have to do now, is to look at the theory you learned and interpret what these values mean.

Sep 05, 2010 | Casio CFX-9850G Plus Calculator

### How do I use the standard deviation function?

1. Calculator must be in SD mode (standard deviation mode) :Press [MODE] [.]
2. However, if [FIX] or [SCI] appears on display you must press [MODE][9] first.
3. Data input always starts with [SHIFT][SAC], to clear the registers of old data.
4. Type a number and press the [DATA] key, it is the [M+] key at the bottom right of keypad.
After you finish entering the data

Press [SHIFT] [9] (sigma n-1) to get sample standard deviation
Press [SHIFT][8] (sigma n] for the population standard deviation
Press [SHIFT] [7] (xbar) for the mean
Press [SHIFT] [6] (n) for the number of data entries
Press [SHIFT] [5] (capital sigma x) for the sum of values
Press [SHIFT] [4] (capital sigma x to y) for the sum of squares of the values

For additional information you might consider taking a look at the calculator manual.

Apr 30, 2010 | Casio FX-260 Calculator

### Calculate Variance on Casio FX-83ES Calculator

Hello,
I am happy that you found my solution helpful and even flattered that you copied it in this thread. By doing this, you gave me the opportunity to discover an error in my post. In fact, the calculator does provide a column for the frequency. If you enter nothing in the frequency column, all data items will have their frequency set to 1, by default.

Back to the current subject: How to get the variance (the square of the standard deviation).
When you finish entering your data:
1. Press the [AC] button to exit the data editor.
2. Press [****][STAT].
3. Press [5:Var] to open the statistical result selection screen.
4. Press [3: xSigma_n] or [4:xSigma_n -1] depending on what you are interested in (population or sample) standard deviation.
5. The screen echoes the symbol for the value selected (the value displayed on the bottom line may be 0 or an old value from a previous calculation: it is not the value you have just calculated).
6. Press [=] to display the current value of the SD chosen.
7. By doing this you are in fact storing it it answer memory.
8. All you have to do now is to raise it to power 2 by pressing the [x^2] key ( the one above the [HYP] key).
9. The calculator will display Ans^2.
10. Press [=] to display the value of the variance.
If you are not interested in the value of the standard deviation, but just want the variance, follow the foregoing procedure until step #5.
While the symbol xSigma_n or xSigma_n-1 is still displayed with the blinking cursor to its right, press the [x^2] key above the [HYP] key. The screen displays say xSigma_n ^2. Press [=] to calculate the variance.

As my motto says, I am always happy to help, but happier still when people show true appreciation.

Hope it helps.

Dec 11, 2009 | Casio fx-300ES Calculator

### How do i find the variance if i'm given the x

Hello,
Set the [Mode] to [3:STAT]. You are offered the choices
1:1-Var
2:A+BX
3:__+cX^2
etc.
If you want to do 1-Var statistics, you press 1:1-Var. A column template opens where you put the X values. If a value is repeated you enter it several times. (there is no frequency column.)
When you enter all data you press [SHIFT][STAT]

You have several choices among them
4: SUM to get SigmaX^2 and Sigma X
5: VAR to get n, the mean X bar, the sample and population standard deviations
6:MINIMAX to get MinX and MaxX
7: Distr the Distributions.

If you want to perform 2-Var statistics
You press [MODE][STAT] and select one of the Regression models
2:A+BX
3:__+cX^2
etc.
The selection of any of the 7 regression models, opens a two-column template where you enter the X and Y values
When finished press [SHIFT][STAT]
The choices offered are
1. Type takes you back to select type of statistics to perform
2. Data To edit the data in the columns
3. Edit To insert or delete a value
4. SUM To access the calculated values of SigX^2,SigX,SigY^2,SigY,SigXY,SigX^3, SigX^2Y, SigX^4
5. Var : To access the calculated values n, Xbar, Sample STD for x, S STD for Y, Pop STD for X, and Pop STD for Y
6. MinMax : MinX, MinY, MaxX, MaxY
7. Reg: Gives you the regression coefficients for the particular regression model you want to test.
The mean is represented by X bar.
The variance is the SQUARE of the Standard Deviation.
Hope it helps.

Nov 06, 2009 | Casio fx-300ES Calculator

### Standard deviation

standard deviation

calculate mean of a data set:

1. Turn calc. on or press MODE SeTUP
2.Press 3 for STAT
3. Press 1 for VAR
4.Enter values for X column
5. WHen done entering press SHIFT 1
6.Press 5
7.Press 2 to calculate the mean
8.Press =

Oct 05, 2008 | Casio FX-115ES Scientific Calculator

### Standard Deviations

This calc will do standard deviations. In the manual it is on page 2 and also on page 40.

Sep 07, 2006 | Casio FX-7400G Plus Calculator

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