fx-82MS fx-83MS fx-85MS fx-270MS fx-300MS fx-350MS

User's Guide

http://world.casio.com/edu/
CASIO ELECTRONICS CO., LTD. Unit 6, 1000 North Circular Road, London NW2 7JD, U.K.
Removing and Replacing the Calculators Cover
Before starting..1 Holding the cover as shown in the illustration, slide the unit out of the cover. After you are finished..2 Holding the cover as shown in the illustration, slide the unit out of the cover. Always slide the keyboard end of the unit into the cover first. Never slide the display end of the unit into the cover.

Safety Precautions

Be sure to read the following safety precautions before using this calculator. Keep this manual handy for later reference.

Caution

This symbol is used to indicate information that can result in personal injury or material damage if ignored.

Batteries

After removing the battery from the calculator, put it in a safe place where it will not get into the hands of small children and accidentally swallowed. Keep batteries out of the reach of small children. If accidentally swallowed, consult with a physician immediately. Never charge batteries, try to take batteries apart, or allow batteries to become shorted. Never expose batteries to direct heat or dispose of them by incineration. Misuse of batteries can cause them to leak and damage nearby items, and can create the risk of fire and personal injury. Always make sure that the batterys positive k and negative l ends are facing correctly when you load it into the calculator. Remove the battery if you do not plan to use the calculator for a long time (fx-82MS/fx-83MS/fx270MS/fx-350MS). Use only the type of battery specified for this calculator in this manual.
Disposing of the Calculator
Never dispose of the calculator by burning it. Doing so can cause certain components to suddenly burst, creating the risk of fire and personal injury. The displays and illustrations (such as key markings) shown in this Users Guide are for illustrative purposes only, and may differ somewhat from the actual items they represent. E-2
The contents of this manual are subject to change without notice. In no event shall CASIO Computer Co., Ltd. be liable to anyone for special, collateral, incidental, or consequential damages in connection with or arising out of the purchase or use of these materials. Moreover, CASIO Computer Co., Ltd. shall not be liable for any claim of any kind whatsoever against the use of these materials by any other party.

Handling Precautions

Be sure to press the 5 key before using the calculator for the first time. Even if the calculator is operating normally, replace the battery at least once every three years for the fx83MS/fx-85MS/fx-270MS/fx-300MS/fx-350MS, or at least once every two years for the fx-82MS. A dead battery can leak, causing damage to and malfunction of the calculator. Never leave a dead battery in the calculator. The battery that comes with this unit discharges slightly during shipment and storage. Because of this, it may require replacement sooner than the normal expected battery life. Low battery power can cause memory contents to become corrupted or lost completely. Always keep written records of all important data. Avoid use and storage in areas subjected to temperature extremes. Very low temperatures can cause slow display response, total failure of the display, and shortening of battery life. Also avoid leaving the calculator in direct sunlight, near a window, near a heater or anywhere else it might be exposed to very high temperatures. Heat can cause discoloration or deformation of the calculators case, and damage to internal circuitry. Avoid use and storage in areas subjected to large amounts of humidity and dust. Take care never to leave the calculator where it might be splashed by water or exposed to large amounts of humidity or dust. Such conditions can damage internal circuitry. E-3
Never drop the calculator or otherwise subject it to strong impact. Never twist or bend the calculator. Avoid carrying the calculator in the pocket of your trousers or other tight-fitting clothing where it might be subjected to twisting or bending. Never try to take the calculator apart. Never press the keys of the calculator with a ballpoint pen or other pointed object. Use a soft, dry cloth to clean the exterior of the calculator. If the calculator becomes very dirty, wipe it off with a cloth moistened in a weak solution of water and a mild neutral household detergent. Wring out all excess moisture before wiping the calculator. Never use thinner, benzene or other volatile agents to clean the calculator. Doing so can remove printed markings and can damage the case.

Contents

Removing and Replacing the Calculators Cover.. 1 Safety Precautions.. 2 Handling Precautions.. 3 Two-line Display.. 7 Before getting started.. 7
kModes... 7 kInput Capacity... 8 kMaking Corrections During Input.. 8 kReplay Function... 9 kError Locator... 9 kMulti-statements.. 9 kExponential Display Formats. 10 kDecimal Point and Separator Symbols. 10 kInitializing the Calculator.. 11

Basic Calculations.. 11

kArithmetic Calculations... 11 kFraction Operations... 11 kPercentage Calculations.. 13 kDegrees, Minutes, Seconds Calculations. 14 kFIX, SCI, RND... 15

Memory Calculations.. 16

kAnswer Memory... kConsecutive Calculations. kIndependent Memory.. kVariables.. 16 17
Scientific Function Calculations.. 17
kTrigonometric/Inverse Trigonometric Functions. 18 kHyperbolic/Inverse Hyperbolic Functions. 18 E-5
kCommon and Natural Logarithms/ Antilogarithms.. 19 kSquare Roots, Cube Roots, Roots, Squares, Cubes, Reciprocals, Factorials, Random Numbers, , and Permutation/Combination.. 19 kAngle Unit Conversion... 20 kCoordinate Conversion (Pol (x, y), Rec (r, )).. 20 kEngineering Notation Calculations.. 21
Statistical Calculations.. 21
Standard Deviation.. 21 Regression Calculations.. 24
Technical Information.. 28
kWhen you have a problem.. kError Messages... kOrder of Operations.. kStacks... kInput Ranges.. 32
Power Supply.. 34 Specifications.. 37

Two-line Display

The two-line display makes it possible to view both the calculation formula and its result at the same time.
The upper line shows the calculation formula. The lower line shows the result. A separator symbol is displayed every three digits when the integer part of the mantissa has more than three digits.

Before getting started.

k Modes
Before starting a calculation, you must first enter the correct mode as indicated in the table below. To perform this type of calculation: Basic arithmetic calculations Standard deviation Regression calculations Perform this To enter key operation: this mode:

F1 F2 F3

COMP SD REG
Pressing the F key more than once displays additional setup screens. Setup screens are described in the sections of this manual where they are actually used to change the calculator setup. In this manual, the name of the mode you need to enter in order to perform the calculations being described is indicated in the main title of each section. Example:

Statistical Calculations

SD REG
To return the calculation mode and setup to the initial defaults shown below, press A B 2(Mode) =. Calculation Mode: Angle Unit: Exponential Display Format: Fraction Display Format: Decimal Point Character: COMP Deg Norm 1 a b/c Dot
Mode indicators appear in the upper part of the display. Be sure to check the current calculation mode (SD, REG, COMP) and angle unit setting (Deg, Rad, Gra) before beginning a calculation.

k Input Capacity

The memory area used for calculation input can hold 79 steps. One step is taken up each time you press a number key or arithmetic operator key ( +, ,, -, \ ). A A or p key operation does not take up a step, so inputting A D, for example, takes up only one step. You can input up to 79 steps for a single calculation. Whenever you input the 73rd step of any calculation, the cursor changes from _ to k to let you know memory is running low. If you need to input more than 79 steps, you should divide your calculation into two or more parts. Pressing the g key recalls the last result obtained, which you can use in a subsequent calculation. See Answer Memory for more information about using the g key.
k Making Corrections During Input
Use e and r to move the cursor to the location you want. Press [ to delete the number or function at the current cursor position. Press A K to change to an insert cursor t. Inputting something while the insert cursor is on the display inserts the input at the insert cursor position. Pressing A K, or = returns to the normal cursor from the insert cursor.

k Replay Function

Display the selection screen.
Press the number key ( 1 or 2) that corresponds to the setting you want to use.
1(Dot): Period decimal point, comma separator 2(Comma): Comma decimal point, period separator
k Initializing the Calculator
Perform the following key operation when you want to initialize the calculation mode and setup, and clear replay memory and variables.

A B 3(All) =

Basic Calculations
k Arithmetic Calculations
Use the F key to enter the COMP Mode when you want to perform basic calculations. COMP... F 1 Negative values inside of calculations must be enclosed within parentheses. For details, see Order of Operations. It is not necessary to enclose a negative exponent within parentheses. sin 2.S 2.34 e D 5 Example 1: 3(5109) 1.5108 3-5eD9= Example 2: 5(97) 80 5-R9+7T= You can skip all T operations before =.

k Fraction Operations

uFraction Calculations
Values are displayed in decimal format automatically whenever the total number of digits of a fractional value (integer + numerator + denominator + separator marks) exceeds 10.

Example 1:

2C3+1C5=

13 15.00

11 Example 2: 3C1C4+ 1C2C3= Example 3: 1 Example 4: 1.6 2.1 2

2C4= 1 C 2 + 1.6 =

Results of calculations that mix fraction and decimal values are always decimal.
uDecimal Fraction Conversion
Use the operation shown below to convert calculation results between decimal values and fraction values. Note that conversion can take as long as two seconds to perform. Example 1: 2.3 (Decimal Fraction) 4 2.75 = 2.75

4.4.00

1 Example 2: 0.5 (Fraction Decimal) 2 1C2=

1 2.00 0.2.00

uMixed Fraction Improper Fraction Conversion

Example: 3 1C2C3=

3.3.2 3.00
You can use the display setup (Disp) screen to specify the display format when a fraction calculation result is greater than one. To change the fraction display format, press the q key a number of times until you reach the setup screen shown below.
Display the selection screen. Press the number key ( 1 or 2) that corresponds to the setting you want to use.

1(a b/c): Mixed fraction 2(d/c): Improper fraction
An error occurs if you try to input a mixed fraction while the d/c display format is selected.
k Percentage Calculations
Example 1 : To calculate 12% of 1500 (180) 1500 - 12 A v Example 2: To calculate what percentage of 880 is 660 (75%) 660 \ 880 A v Example 3 : To add 15% onto 2500 (2875) 2500 - 15 A v + Example 4 : To discount 3500 by 25% (2625) 3500 - 25 A v , E-13
Example 5: To discount the sum of 168, 98, and 734 by 20% (800) 168 + 98 + 734 = g A j 1 * As shown here, if you want to use the current Answer Memory value in a mark up or discount calculation, you need to assign the Answer Memory value into a variable and then use the variable in the mark up/discount calculation. This is because the calculation performed when v is pressed stores a result to Answer Memory before the , key is pressed. Example 6: If 300 grams are added to a test sample originally weighing 500 grams, what is the percentage (160%) increase in weight? 300 + 500 A v Example 7: What is the percentage change when a value is increased from 40 to 46? How about to 48? (15%, 20%) 46 , 40 A v eeeeee8=

p 1 - 20 A v , *

k Degrees, Minutes, Seconds Calculations
You can perform sexagesimal calculations using degrees (hours), minutes, and seconds, and convert between sexagesimal and decimal values. Example 1: To convert the decimal value 2.258 to a sexagesimal value and then back to a decimal value 2.258 =

2.258 21528.8 2.258

Example 2: To perform the following calculation: 123456 3.I 34 I 56 I - 3.45 = E-14

432431.2

k FIX, SCI, RND
To change the settings for the number of decimal places, the number of significant digits, or the exponential display format, press the F key a number of times until you reach the setup screen shown below.
Press the number key ( 1, 2, or 3) that corresponds to the setup item you want to change.
1 (Fix): Number of decimal places 2 (Sci): Number of significant digits 3 (Norm): Exponential display format

Example 1: \ 7 - 14 =

(Specifies three decimal places.)

400.00

F.. 1(Fix) 3

200 \ 7 =

400.00000 28.57100 400.00000
(Internal calculation continues using 12 digits.)

- 14 =

The following performs the same calculation using the specified number of decimal places. 200 \ 7 =

(Internal rounding)

28.57100 28.57100 399.99400

AQ - 14 =

Press F.. 3(Norm) 1 to clear the Fix specification. Example 2: 1 3, displaying result with two significant digits (Sci 2)

F.. 2(Sci) \ 3 =

Press F.. 3(Norm) 1 to clear the Sci specification. E-15

Memory Calculations

Use the F key to enter the COMP Mode when you want to perform a calculation using memory. COMP... F 1

k Answer Memory

Whenever you press = after inputting values or an expression, the calculated result automatically updates Answer Memory contents by storing the result. In addition to =, Answer Memory contents are also updated with result whenever you press A v, |, A {, or A j followed by a letter (A through F, or M, X, or Y). You can recall Answer Memory contents by pressing g. Answer Memory can store up to 12 digits for the mantissa and two digits for the exponent. Answer Memory contents are not updated if the operation performed by any of the above key operations results in an error.
k Consecutive Calculations
You can use the calculation result that is currently on the display (and also stored in Answer Memory) as the first value of your next calculation. Note that pressing an operator key while a result is displayed causes the displayed value to change to Ans, indicating it is the value that is currently stored in Answer Memory. The result of a calculation can also be used with a subsequent Type A function (x2, x3, x1, x!, DRG'), +, , ^(xy), x , , , nPr and nCr.

k Independent Memory

Values can be input directly into memory, added to memory, or subtracted from memory. Independent memory is convenient for calculating cumulative totals. Independent memory uses the same memory area as variable M. To clear independent memory (M), input 0 A j 3 (M+). E-16
Example: ) 90 (Total) 23 + 9 A j 3 (M+) 53 , 6 | 45 - 2 A {

k Variables

There are nine variables (A through F, M, X and Y), which can be used to store data, constants, results, and other values. Use the following operation to delete data assigned to a particular variable: 0 A j 1. This operation deletes the data assigned to variable A. Perform the following key operation when you want to clear the values assigned to all of the variables.

A B 1(Mcl) =

Example: 193.8.4 193.6.9 193.2 A j 1 \ 23 =

p 1 \ 28 =

Scientific Function Calculations
Use the F key to enter the COMP Mode when you want to perform scientific function calculations. COMP... F 1 Certain types of calculations may take a long time to complete. Wait for the result to appear on the display before starting the next calculation. = 3.14159265359
k Trigonometric/Inverse Trigonometric Functions
To change the default angle unit (degrees, radians, grads), press the F key a number of times until you reach the angle unit setup screen shown below.

Deg Rad G r a

Press the number key ( 1, 2, or 3 ) that corresponds to the angle unit you want to use. (90 =

radians = 100 grads)

Example 1: sin 6352o41 0.897859012

q.. 1 (Deg) S 63 I 52 I 41 I =

Example 2: cos

rad 0.5 3

q.. 2 (Rad) WRAx\3T=

Example 3 : cos1
2 (rad) 0.25 (rad) 2 4.. 2 (Rad) q

AVRL2\2T=g\Ax=

Example 4: tan1 0.741 36.53844577

q.. 1 (Deg) A g 0.741 =

k Hyperbolic/Inverse Hyperbolic Functions
Example 1: sinh 3.6 18.28545536 Example 2: sinh

M S 3.6 = M A j 30 =

30 4.094622224
k Common and Natural Logarithms/ Antilogarithms
Example 1: log 1.23 0.089905111
R 1.23 = T 90 = TpP= A U 10 = A Q 1.5 =
Example 2: In 90 (= loge 90) = 4.49980967 ln e 1 Example 3: e10 22026.46579 Example 4: 10 31.6227766
Example 5: 23 0.125 Example 6: (2)4 16

RD2TW4=

Negative values inside of calculations must be enclosed within parentheses. For details, see Order of Operations.
k Square Roots, Cube Roots, Roots, Squares, Cubes, Reciprocals, Factorials, Random Numbers, , and Permutation/Combination

5 5.287196909

L2+L3-L5=

Example 2: 1.290024053

A D 5 + A D R D 27 T =

Example 3:

123 ( = ) 1.A H 123 =

Example 4: 1023

123 + 30 K = 12 N =
Example 5: 1 Example 6: 4 Example 7: 8! 40320

R3a,4aTa=

Example 8: To generate a random number between 0.000 and 0.999

Example 9: 3 9.424777961

0.66400
(The above value is a sample only. Results differ each time.)
Example 10: To determine how many different 4-digit values can be produced using the numbers 1 through 7 Numbers cannot be duplicated within the same 4-digit (840) value (1234 is allowed, but 1123 is not). 7Am4= Example 11: To determine how many different 4-member groups can be organized in a group of 10 individuals (210) 10 n 4 =

k Angle Unit Conversion

Press A v to display the following menu.
Pressing 1, 2, or 3 converts the displayed value to the corresponding angle unit. Example: To convert 4.25 radians to degrees
q.. 1(Deg) 4. 25 r 4.25 A v 2(R) = 243.5070629
k Coordinate Conversion (Pol (x, y), Rec (r, ))
Calculation results are automatically assigned to variables E and F. Example 1: To convert polar coordinates (r2, 60) to rectangular coordinates (x, y) (Deg) x1 y 1.732050808

A F 2 P 60 T = 0o

Press 0 n to display the value of x, or 0 o to display the value of y. E-20
Example 2: To convert rectangular coordinates (1, 3) to polar coordinates (r,) (Rad) r2

1.047197551

f1P L3T= 0o
Press 0 n to display the value of r, or 0 o to display the value of.
k Engineering Notation Calculations
Example 1: To convert 56,088 meters to kilometers 56.3 (km) 81.3 (mg) 56088 = J
Example 2: To convert 0.08125 grams to milligrams 0.08125 = J

Standard Deviation

SD REG SD
Use the F key to enter the SD Mode when you want to perform statistical calculations using standard deviation. SD.. F 2 In the SD Mode and REG Mode, the | key operates as the S key. Always start data input with A B 1 (Scl) = to clear statistical memory. Input data using the key sequence shown below. <x-data> S Input data is used to calculate values for n, x, x2, o, n and n-1, which you can recall using the key operations noted nearby.
To recall this type of value:
Perform this key operation:

x2 x n o n n-1

AU1 AU2 AU3 AX1 AX2 AX3
Example: To calculate n1, n, o, n, x, and x2 for the following data : 55, 54, 51, 55, 53, 53, 54, 52 In the SD Mode: A B 1 (Scl) = (Stat clear) 55 S
Each time you press S to register your input, the number of data input up to that point is indicated on the display (n value).
54 S 51 S 55 S 53 S S 54 S 52 S
Sample Standard Deviation (n1) = 1.407885953 Population Standard Deviation (n) = 1.316956719 Arithmetic Mean (o) = 53.375 Number of Data (n) = 8 Sum of Values (x) = 427 Sum of Squares of Values (x2 ) = 22805
AX3= AX2= AX1= AU3= AU2= AU1=
Data Input Precautions S S inputs the same data twice.
You can also input multiple entries of the same data using A G. To input the data 110 ten times, for example, press 110 A G 10 S. You can perform the above key operations in any order, and not necessarily that shown above. While inputting data or after inputting data is complete, you can use the [ and ] keys to scroll through data you have input. If you input multiple entries of the same data using A G to specify the data frequency (number of data items) as described above, scrolling through data shows both the data item and a separate screen for the data frequency (Freq). E-22

x2 x n y2 y xy o xn xn-1 p yn yn-1
Regression coefficient A Regression coefficient B Regression calculation other than quadratic regression Correlation coefficient r
AU1 AU2 AU3 AUr1 AUr2 AUr3 AX1 AX2 AX3 AXr1 AXr2 AXr3 AXrr1 AXrr2

AXrr3 AXrrr1 AXrrr2

The following table shows the key operations you should use to recall results in the case of quadratic regression.
To recall this type of value: Perform this key operation:

x3 x2y x4

Regression coefficient C

m1 m2 n

AUrr1 AUrr2 AUrr3 AXrr3 AXrrr1 AXrrr2 AXrrr3
The values in the above tables can be used inside of expressions the same way you use variables.

u Linear Regression

The regression formula for linear regression is: y = A + Bx. E-25
Example: Atmospheric Pressure vs. Temperature Temperature Atmospheric Perform linear regression to dePressure termine the regression formula 10C 1003 hPa terms and correlation coefficient 15C 1005 hPa for the data nearby. Next, use 20C 1010 hPa the regression formula to esti25C 1011 hPa mate atmospheric pressure at 30C 1014 hPa 5C and temperature at 1000 hPa. Finally, calculate the coefficient of determination ( r 2 ) and sample covariance. In the REG Mode:
1(Lin) A B 1 (Scl) = (Stat clear)

10 P1003 S

15 P 1005 S 20 P1010 S 25 P 1011 S 30 P 1014 S
Regression Coefficient A = 997.4 Regression Coefficient B = 0.56 Correlation Coefficient r = 0.982607368 Atmospheric Pressure at 5C = 994.6

AXrr1= AXrr2= AXrr3=

ED5FAXrrr2=
Temperature at 1000 hPa = 4.642857143

1000 A X r r r 1 =

Coefficient of Determination = 0.965517241

Sample Covariance = 35

AXrr3K= EAUr3, AU3-AX1AXr1F\ EAU3,1F=
u Logarithmic, Exponential, Power, and Inverse Regression
Use the same key operations as linear regression to recall results for these types of regression. The following shows the regression formulas for each type of regression. Logarithmic Regression Exponential Regression Power Regression Inverse Regression y A B In x y A eBx (In y In A + Bx) y A xB (In y In A + BIn x) y A B 1/x

u Quadratic Regression

The regression formula for quadratic regression is: y = A + Bx + Cx2. Example:

Syntax ERROR

Cause An attempt to perform an illegal mathematical operation. Action Press e or r to display the calculation with the cursor located at the location of the error and make required corrections.

Arg ERROR

Cause Improper use of an argument Action Press e or r to display the location of the cause of the error and make required corrections.

k Order of Operations

Calculations are performed in the following order of precedence. 1 Coordinate transformation: Pol (x, y), Rec (r, ) 2 Type A functions: With these functions, the value is entered and then the function key is pressed. x3, x2, x1, x!, m, m1, m2, n Angle unit conversions (DRG') 3 Powers and roots: ^ (xy), x 4 a b/c 5 Abbreviated multiplication format in front of , e (natural logarithm base), memory name, or variable name: 2, 3e, 5A, A, etc. 6 Type B functions: With these functions, the function key is pressed and then the value is entered. 3 , , log, In, ex, 10x, sin, cos, tan, sin1, cos1, tan1, sinh, cosh, tanh, sinh1, cosh1, tanh1, () 7 Abbreviated multiplication format in front of Type B functions: 2 3, Alog2, etc. 8 Permutation and combination: nPr, nCr 9 , 0 , Operations of the same precedence are performed from 120 ex{In( 120)} right to left. exIn Other operations are performed from left to right. Operations enclosed in parentheses are performed first. When a calculation contains an argument that is a negative number, the negative number must be enclosed within parentheses. The negative sign () is treated as a Type B function, so particular care is required when the calculation includes a high-priority Type A function, or power or root operations. Example: ( 2)4 = = 16

k Stacks

This calculator uses memory areas, called stacks, to temporarily store values (numeric stack) and commands (command stack) according to their precedence during calculations. The numeric stack has 10 levels and the command stack has 24 levels. A stack error (Stack ERROR) occurs whenever you try to perform a calculation that is so complex that the capacity of a stack is exceeded. Example:

Numeric Stack 5 4

Command Stack
Calculations are performed in sequence according to Order of Operations. Commands and values are deleted from the stack as the calculation is performed.

k Input Ranges

Internal digits: 12 Accuracy*: As a rule, accuracy is 1 at the 10th digit. Functions sinx Input Range DEG 0 x 4.4999999991010 RAD 0 x 785398163.3 GRA 0 x 4.9999999991010 cosx DEG 0 x 4.5000000081010 RAD 0 x 785398164.9 GRA 0 x 5.0000000091010 tanx DEG Same as sinx, except when x= (2n-1)90. RAD Same as sinx, except when x= (2n-1)/2. GRA Same as sinx, except when x= (2n-1)100. sin1x cos1x tan1x sinhx coshx 0 x x 9.x 230.2585092
sinh1x 0 x 4.9999999991099 cosh1x 1 x 4.9999999991099 tanhx

0 x 9.9999999991099

tanh x 0 x 9.999999999101 logx/lnx 0 x 9.9999999991099 10x 9.9999999991099 x 99.99999999 9.9999999991099 x 230.x x x ; x G 0 x 0 x 69 (x is an integer) 0 n 11010, 0 r n (n, r are integers) 1 {n!/(nr)!} 110100 E-32

ex x x2 1/x 3 x x!

Functions
Input Range 0 n 11010, 0 r n (n, r are integers) 1 [n!/{r!(nr)!}] 110100
49 Pol(x, y) x, y 9.99999999910 (x2+y2) 9.Rec(r, ) 0 r 9.99999999910 : Same as sinx a, b, c 110100 0 b, c x110100 Decimal Sexagesimal Conversions 000 x 99999959 x0: 110100ylogx100 ^(xy) x0: yx0: yn, 2n+1 (n is an integer) However: 110100 ylogx100

y0: x G 0

1101001/x logy100 y0: xy0: x2n1, n (n G 0; n is an integer) However: 110100 1/x logy100 Total of integer, numerator, and denominator must be 10 digits or less (including division marks). x 11050 y 11050 n 110100

SD (REG)

xn, yn, o, p : n G 0 xn1, yn1, A, B, r : n G 0, 1
* For a single calculation, calculation error is 1 at the 10th digit. (In the case of exponential display, calculation error is 1 at the last significant digit.) Errors are cumulative in the case of consecutive calculations, which can also cause them to become large. (This is also true of internal consecutive calculations that are performed 3 x , nPr, nCr, etc.) in the case of ^(x y), y , x!, In the vicinity of a functions singular point and point of inflection, errors are cumulative and may become large. E-33

Power Supply

The type of battery you should use depends on the model number of your calculator.

fx-85MS/fx-300MS

The TWO WAY POWER system actually has two power supplies: a solar cell and a G13 Type (LR44) button battery. Normally, calculators equipped with a solar cell alone can operate only when relatively bright light is present. The TWO WAY POWER system, however, lets you continue to use the calculator as long as there is enough light to read the display.

Replacing the Battery

Either of the following symptoms indicates battery power is low, and that the battery should be replaced. Display figures are dim and difficult to read in areas where there is little light available. Nothing appears on the display when you press the 5 key.

u To replace the battery

1 Remove the six screws that hold the back cover in place and then remove the back cover. 2 Remove the old battery. 3 Wipe off the sides of new battery with a dry, soft cloth. Load it into the unit with the positive k side facing up (so you can see it). 4 Replace the back cover and secure it in place with the six screws. 5 Press 5 to turn power on. Be sure not to skip this step.

Screw Screw

fx-83MS/fx-270MS/fx-350MS
This calculator is powered by single G13 Type (LR44) button battery.
Dim figures on the display of the calculator indicate that battery power is low. Continued use of the calculator when the battery is low can result in improper operation. Replace the battery as soon as possible when display figures become dim.

To replace the battery

1 Press A i to turn off power. 2 Remove the screw that holds the battery cover in place and then remove the battery cover. 3 Remove the old battery. 4 Wipe off the sides of new battery with a dry, soft cloth. Load it into the unit with the positive k side facing up (so you can see it). 5 Replace the battery cover and secure it in place with the screw. 6 Press 5 to turn power on.