Review: Casio
fx-55 Plus
General Information
Company: Casio
Type: Fractions,
Elementary Math
Memory: 1
Battery: Solar with
battery backup (1 LR44)
Years: 2012 - current
Cost: $10.00 - $20.00,
I paid $12.99
Operating Logic:
Algebraic
Target Audience:
* Elementary and middle school students
* Anyone who wants a few more functions than the regular
four-function calculator, but not a scientific calculator
* You want a calculator with an emphasis on fractions
Features
The major emphasis on the Casio fx-55 Plus is on
fractions. We’ll discuss this in the
next section in detail.
The screen has a textbook display, meaning fractions and all
other calculations are displayed as you would write them. Fractions are simplified. If MathO (Math Output) is selected, square
roots and terms of pi (π) shown in exact form.
If LineO is selected, all answers (except fractions) are shown in
decimal form. No matter what the display mode is,
you can always decimal approximation by pressing [SHIFT] [ = ].
Example (MathO):
√12 returns 2 √3
5^2 * π returns 25π
You enter expressions the way you would write them with the
Casio fx-55 Plus. The display is a
mutli-line display, the expression on the top of the screen and the answer is
on the bottom of the screen.
The keyboard is simple where only four keys have shifted
functions. The OFF function is shifted
as well.
Other functions include reciprocal, random numbers,
including random integers, and calculations in Degrees-Minutes-Seconds [ ° ‘ “
].
The memory has four dedicated keys: store, recall, add to
memory (M+), and subtract from memory (M-).
The percent keys work a bit differently from the normal
four-function calculators (and is not very intuitive).
[%] divides the argument by 100 and that’s it. Its fine when you are working with multiplying
or dividing percentages, but adding and subtracting percent will take an
algorithm:
X + Y%: enter X + X *
Y %
X – Y%: enter X – X *
Y %
[>%] multiplies the result by 100 and displays the answer
in percentage notation.
Example: 3 [ = ] [
SHIFT ] (>%) returns 300%
Let’s Talk Fractions
The fraction keys are marked lime green on the Casio fx-55
Plus. Let’s go over the keys in detail:
[ []/[] ] (1st key from the left): fraction template
[ [] []/[] ] (2nd key from the left): mixed number template
[ F←→D] (3rd key from the left): switches the
result between exact (fractions, exact square roots, terms of π) and decimal
answer
[ a b/c ←→ d/c ]: (4th key from the left)
Manual Simplified mode:
This key does nothing.
Auto Simplified mode: This key converts the result between
improper and proper fraction notation.
[ Simp ]: calls the
simplify conversion to the entry. In
Manual Simplified mode, any fraction that is not reduced to its irreducible form
will have a down arrow indicator ( ↓ ). Also executing Simp in Manual Simplified mode
not only returns the reduced fraction, but the factor used into reducing such
fraction.
[x^-1]: The reciprocal
function
I also want to point a very handy key, the remainder
division function ( [÷R]), which is located on the bottom right hand corner of
the keyboard. This function returns both
the quotient and remainder.
Example: 77 ÷R 13
returns 5, R = 12
Only the quotient is stored in last answer (Ans).
Let’s compare this Casio fx-55 Plus with an older fraction
oriented calculator, the Texas Instruments Math Explorer (aka TI-12).
Comparison: Casio fx-55
Plus (2012-present) vs. Texas Instruments Math Explorer (1978-1998)
|
TI Math Explorer
|
Casio fx-55 Plus
|
|
1 line display
|
Multi-line, textbook display
|
|
No shifted functions
|
4 shifted functions
|
|
N/A
|
Degrees-Minutes Seconds calculations, random numbers and
integers
|
|
Constant arithmetic storage function through the [ Cons ]
key.
|
N/A
|
|
10^n is limited to integers 0-7
|
10^x allows for all real numbers between up to, but not
including, 100. Used to work with
numbers in scientific notation
|
|
Int÷ works with only positive integers
|
÷R works with real, positive numbers (any non-positive
numbers makes ÷R work like ÷)
|
Verdict
I like this calculator for middle school and elementary students.
The Casio fx-55 Plus presents a few extra functions but without the many
scientific functions that may intimidate some students. (emphasis on some) I wish the percent would work like we would
write expressions when it comes to addition or subtraction (i.e. X + Y% instead
of X + X * Y%), but this is understandable.
I also wish the proper/improper toggle worked in Manual Simplified mode.
The display is great because the user can see the expression
and answer at the same time. I really
like that this calculator also returns exact answers in calculations involving
square roots and π.
I can see this calculator being used beyond the classroom,
especially in everyday basic math calculations.
In any case, the Casio fx-55 Plus serves a great introductory
calculator.
Eddie
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Shore. Unauthorized use and/or
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