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The Calculator File.
The following operations can be done on the calculator
some of which you may know already.
(1)
The calculator knows the rules of algebra, so if you are in any way dodgy with
your minus signs and brackets or have a difficulty with fractions use your
calculator!
(2)
Note the 
key just changes the
sign of a number; be careful not to mix this key with the minus key!
(3)
Example if you want to find 3 - -7 the
best way is to do this 3-7
=10.
If you
want to find the value of 
do it this way 
the answer is 16.
Do not leave out the equals Sign!
The calculator has been taught the rules of BOMDAS
i.e. it will always multiply or divide before it adds or subtracts!
Fractions. The 
key is the fraction key, if we call this key
F, to put 7/6 on the calculator we just press 7F6 it will appear as 7 r 6, if
you want 
just input 5F3F4 it will look like 5 r 3 r 4 on the calculator.
So to find the value of 
it is done as follows (7F6+4F5)
(4F3-1F2) =
A bit of practice using this key will get rid of all
your fear of fractions (the brackets here are very important)
Scientific Notation the EXP key. This key is use to evaluate problems involving Scientific notation.
Evaluate 
. This is done as follows 3.5 EXP 5 divided by 4.2EXP 3 =
Is you were asked to evaluate 
, we do this as follows
7.6 EXP 
x 4.6 EXP 6 =.
Statistics The mean and standard Deviation.
The method used to find the mean and standard deviation
varies from calculator. But here are the methods for three of the more popular
calculators
(1)
Sharp DAL (older model).
Step 1 press mode the calculator shows
0 –1 then press 1 the word STAT will appear on the screen
We will
work using the following frequency table.
|
Number |
1 |
2 |
3 |
4 |
|
Frequency |
5 |
7 |
6 |
2 |
Step 2. 
(Number by frequency
M+)
The calculator should show 20 at this stage. The sharp model
always shows the sum of the frequency at each stage.
Step 3
to find the mean press 2nd function (left bracket)
Step 4
to find the standard deviation press 2nd function division sign 
.
(2)
For the Sharp
Advanced DAL
this is the one, which has the words STO and RCL (in green or purple).
The method is similar to above but you will use the STO, M+, RCL
keys this time
Step (1)
Press mode; 0-2 appears, press 0 in some models you press 1,
Stat
appears on the screen!
Step 2.
Using
the table above 1 STO 5 M+, 2STO7 M+, 3STO 6 M+, 4STO2M+.
Step3.
Mean is RCL 
(the key can vary from “left bracket” to 4
Step 4
Standard Deviation is RCL 
The
Sharp calculators always show you the sum of the frequency after each
step this will tell you that you are working correctly.
For
Older type Casio’s
Mode Stat is mode (SD), which is mode 3/4. See front of calculator
for which mode is the stat mode, then use the same method as for the older
Sharpe type The mean is often found on the 7 key, with the standard deviation
on the 8 key.
Again this will vary the mean is 
and the standard
deviation is 
Complex Numbers:
On the advanced solar powered Sharp. You can do
calculations in complex numbers:
You use mode 1, and the I key is on the fraction key!