Citizen SRP-285N: Mode 0 - MAIN

E – 11 

File name : CBM_SR285,A_HDBSR285T19_English.doc 

version : 2010/04/26 

Mode 0 - MAIN 

„

Arithmetic Calculations

z

Arithmetic operations are performed by pressing the keys in the 

same sequence as in the expression.    See Example 6. 

z

For negative values, press [ (

−

) ] before entering the value.    See 

Example 7. 

z

For mixed arithmetic operations, multiplication and division are 

given priority over addition and subtraction.    See Example 8. 

z

Results greater than 10

 10

 or less than 10

 -9

 are displayed in 

exponential form.    See Example 9. 

„

Display formats 

z

Decimal places formats are selected by pressing [ 2nd ] [ TAB ] to 

display the menu. To set decimal places to 

n

 ( 

F0123456789

 ),  

enter a 

n

 value directly or press [ 

 ] key while the item is 

underlined. (The default setting is floating point notation 

F

 and the 

n

 value is 

•

 ).    See Example 10. 

z

Even if the number of decimal places is specified, internal 

calculation for a mantissa is performed up to 24 digits, and the 

display value is stored in 10 digits. To round off those values to 

the specified number of decimal places, press [ 2nd ] [ RND ].  

See Example 11~12. 

z

Number display formats are selected by pressing [ 2nd ] 

[ SCI/ENG ] to display the menu. The items on the menu are 

FLO

(for floating point), 

SCI

 ( for scientific), and 

ENG

 (for engineering). 

Press [   ] or [   ] until the desired formats is underlined, and 

then press [ 

 ].  See Example 13. 

(Note) :  The engineering format is similar to the scientific format, 

except the mantissa can have up to three digits left of 

the decimal, instead of only one, and the exponent is 

always a multiple of three. It is useful for engineers to 

convert units based on multiples of 10 

3

. 

z

You can enter a number in mantissa and exponent form by [ EXP ] 

key.  See Example 14. 

„

Parentheses Calculation 

z

Operations inside parentheses are always executed first. The 

calculator can use up to 13 levels of consecutive parentheses in a 

single calculation.    See Example 15. 

z

Closed parentheses occurring immediately before operation of the 

[ 

  ] key may be omitted, no matter how many are required.   

See Example 16. 

E – 12

File name : CBM_SR285,A_HDBSR285T19_English.doc 

version : 2010/04/26 

z

A multiplication sign " x " occurring immediately before an open 

parenthesis can omitted.    See Example 17. 

(Note) :  The calculator can auto-correct abbreviated 

multiplication in front of all functions, except memory 

variables, left parenthesis, type B functions. 

z

Henceforth, abbreviated type will not be used in this manual.  

See Example 18. 

z

The correct result cannot be derived by entering [ ( ] 2 [ + ] 3 [ ) ] 

[ EXP ] 2. Be sure to enter [ x ] 1 between the [ ) ] and [ EXP ] in 

the below example.    See Example 19. 

„

Percentage Calculation

z

[ 2nd ] [ % ] divides the number in the display by 100. You can use 

this key sequence to calculate percentages, add-ons, discounts, 

and percentages ratios.    See Example 20~21. 

„

Continuous calculation function 

z

The calculator enables you to repeat the last operation executed 

by pressing [ 

 ] key for further calculation.  See Example 

22. 

z

Even if calculations are concluded with the [ 

 ] key, the 

result obtained can be used for further calculation.    See Example 

23. 

„

Answer Function 

z

Answer function stores the most recently calculated result. It is 

retained even after the power is turned off. Once a numeric value 

or numeric expression is entered and [ 

 ] is pressed, the 

result is stored by this function.    See Example 24. 

(Note) :  Even if execution of a calculation results in an error, 

however, Answer memory retains its current value. 

„

Logarithm And Antilogarithm

z

The calculator can calculate common and natural logarithms and 

anti-logarithms using [ log ], [ ln ], [ 2nd ] [ 10 

x

 ], and [ 2nd ]   

[ e 

x

 ].    See Example 25~27. 

„

Fraction Calculation

Fraction value display is as follow : 

5 / 12 

Display of 

12

5

56 

∪

 5 /12 

Display of 56

12

5

E – 13 

File name : CBM_SR285,A_HDBSR285T19_English.doc 

version : 2010/04/26 

z

To enter a mixed number, enter the integer part, press [ a 

b

/

c

 ], 

enter the numerator, press [ a 

b

/

c

 ], and enter the denominator ; To 

enter an improper fraction, enter the numerator, press [ a 

b

/

c

 ], and 

enter the denominator.    See Example 28. 

z

During a fraction calculation, if the figure is reducible, a figure is 

reduced to the lowest terms after pressing a function command 

key ( [ + ], [ – ], [ x ] or [    ] ) or the [ 

  ] key. By pressing 

[ 2nd ] [ a 

b

/

c

  d

/

e

 ], the displayed value will be converted to the 

improper fraction and vice versa.    See Example 29. 

z

To convert between a decimal and fractional result, press [ 2nd ] 

[ F

D ] and [ 

 ].  See Example 30. 

z

Calculations containing both fractions and decimals are calculated 

in decimal format.    See Example 31. 

„

Angle Unit Conversion 

z

The angle units (

DEG

, 

RAD

, 

GRAD

) is set by pressing [ DRG ] to 

display the angle menu. The relation among the three angle units 

is : 

180

°

=

π

rad = 200 grad 

Angle conversations ( See Example 32. ) : 

1. Change the default angle settings to the units you want to 

convert to. 

2. Enter the value of the unit to convert. 

3. Press [ DMS ] to display the menu. The units you can select 

are 

°

 (degrees), 

′

 (minutes), 

″

 (seconds), 

r

 (radians), 

g

(gradians) or  DMS (Degrees-Minutes-Seconds). 

4. Choose the units you are converting from. 

5. Press  [ 

 ] twice. 

z

To convert an angle to 

DMS

 notation, select "

DMS

 " which 

converts an entry to 

DMS

 notations, i.e., where 

1

°

30

′

0

″

represents 1 degrees, 30 minutes, 0 seconds.    See Example 33. 

z

To convert a 

DMS

 notation to decimal, select 

°

(degrees), 

′

(minutes), 

″

 (seconds).    See Example 34. 

E – 14

File name : CBM_SR285,A_HDBSR285T19_English.doc 

version : 2010/04/26 

„

Trigonometric / Inverse-Tri. Functions

The calculator provides standard trigonometric functions and inverse 

trigonometric functions - sin, cos, tan, sin 

–1

, cos 

–1

 and tan 

–1

.  See 

Example 35~37. 

(Note) :  When using those keys, make sure the calculator is set 

for the angle unit you want. 

„

Hyperbolic / Inverse-Hyp. Functions

The calculator uses [ 2nd ] [ HYP ] to calculate the hyperbolic 

functions and inverse- hyperbolic functions – sinh, cosh, tanh, 

sinh 

–1

, cosh 

–1

 and tanh 

–1

.  See Example 38~39. 

(Note) :  When using those keys, make sure the calculator is set 

for the angle unit you want. 

„

Coordinates Transformation

Pressing [ 2nd ] [ R

P ] displays a menu to convert rectangular 

coordinates to polar coordinates or vice versa.  See Example 

40~41. 

Rectangular Coordinates   

Polar Coordinates  

x + y i = r (cos

θ

+ i sin

θ

) 

(Note) :  When using those key, make sure the calculator is set 

for the angle unit you want. 

„

Probability 

z

Pressing [ PRB ] displays the probability menu.  See Example 

42~46.    With the following functions : 

nPr 

Calculates the number of possible permutations of n item 

taken r at a time. 

nCr

Calculates the number of possible combinations of n 

items taken r at a time. 

!

Calculates the factorial of a specified positive integer n , 

where n 

≦

 69. 

RANDM

   Generates a random number between 0 and 1. 

RANDMI

  Generates a random integer value between two specified 

integers, A and B, where A 

≦

 random value 

≦

 B 

E – 15 

File name : CBM_SR285,A_HDBSR285T19_English.doc 

version : 2010/04/26 

„

Other Functions ( x

–1

, 

√

, 

X

, x 

2

, ^ )

z

The calculator also provides reciprocal ( [ x 

–1

 ] ), square root 

( [ 

√  

] ), universal root ( [ 

X

 ] ), square ( [ x 

2

 ] ) and 

exponentiation ( [ ^ ] ) functions.    See Example 47~50. 

„

Unit Conversions

z

The calculator has a built-in unit conversion feature that enables 

you to convert numbers from metric to English units and vice 

versa.  See Example 51. 

1.  Enter the number you want to convert. 

2.  Press [ 2nd ] [ CONV ] to display the menu. There are 7 

menus, covering distance, area, temperature, capacity, 

weight, energy, and pressure. 

3.  Use the [   ] [   ] to scroll through the list of units until a 

appropriate units menu is shown, then [ 

 ]. 

4. Pressing 

[  ] or [   ] can convert the number to another 

unit. 

„

Physical Constants 

z

You can use a number of physical constants in your calculations. 

See table below : 

Symbol Meaning 

Value 

c 

Speed of light in vacuum

299792458 m / s 

g 

Acceleration of gravity 

9.80665 m.s 

–2

G Gravitational 

constant 

6.6725985 x 10 

–11

 N.m 

2

 kg 

–2 

Vm 

molar volume of ideal gas 

0.0224141 m 

3

 mol 

–1 

NA 

Avagadro's number 

6.022136736 x 10 

23

mol 

–1

e 

Elementary charge 

1.6021773349 x 10 

–19

 C 

me 

Electron mass 

9.109389754 x 10 

–31

 kg 

mp 

Proton mass 

1.672623110 x 10 

–27

 kg 

h 

Plank's constant 

6.626075540 x 10 

–34

 J.s 

k 

Boltzmann's constant 

1.38065812 x 10 

–23

 J.K 

–1 

R 

Gas constant 

8.3145107 J / mol 

z

k 

F 

Faraday constant 

96485.30929 C / mol 

mn 

Neutron constant 

1.67492861 x 10 

–27

 kg 

µ 

Atomic mass constant 

1.66054021 x 10 

–27

 kg 

ε

0

Dielectric permittivity 

8.854187818 x 10 

–12

 F/m 

µ 

0

Magnetic permittivity 

1.256637061 x 10

–6

 H / m 

φ

0

Flux quantum 

2.0678346161 x 10 

–15

 Vs 

a 

0

Bohr radius 

5.2917724924 x 10 

–11

m 

µB 

Bohr magneton 

9.274015431 x 10 

–24

A

z

m

2

µN 

Neutron magnetic moment 

5.050786617 x 10 

–27

J / T