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CASIO fx-991CW
10-13-2023, 03:23 PM
Post: #101
RE: CASIO fx-991CW
Most of the graphing models are not permitted on standard tests, even through college level exams, to professional level exams like FE, PE, and the like. Unless they plan on developing a new non-graphing scientific calculator, but then why keep the same name? It is just a bad move, happens all the time, companies make mistakes. As most have concluded, as far as Casio is concerned, the FX-991EX and similar models are the way to go. As for me, as an engineer, there are better choices for calculators, which use is now really limited to exams. I do all my calculations using SMath Studio, similar to MathCAD. And perhaps this is why Casio is focusing on middle school math, rather than advanced engineering. There was a day when a calculator was an essential tool for everyday science and engineering, now its just for exams.
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10-13-2023, 04:55 PM
Post: #102
RE: CASIO fx-991CW
(10-13-2023 03:23 PM)wb.c Wrote:  Most of the graphing models are not permitted on standard tests, even through college level exams, to professional level exams like FE, PE, and the like. Unless they plan on developing a new non-graphing scientific calculator, but then why keep the same name? It is just a bad move, happens all the time, companies make mistakes. As most have concluded, as far as Casio is concerned, the FX-991EX and similar models are the way to go. As for me, as an engineer, there are better choices for calculators, which use is now really limited to exams. I do all my calculations using SMath Studio, similar to MathCAD. And perhaps this is why Casio is focusing on middle school math, rather than advanced engineering. There was a day when a calculator was an essential tool for everyday science and engineering, now its just for exams.

As far as the name (model number) is concerned, there is a certain logic to Casio keeping the "115" or "991" in the name of any new non-graphing model in this category.

"Casio - The NCEES approves all fx-115 and fx-991 models for use on its exams. Their policy states that “any Casio calculator must have ‘fx-115 ‘ or ‘fx-991’ in its model name.”"
https://fundamentalsofengineering.com/fe...ators.html
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10-14-2023, 12:33 AM (This post was last modified: 10-14-2023 01:02 AM by Matt Agajanian.)
Post: #103
RE: CASIO fx-991CW
(10-13-2023 04:55 PM)Steve Simpkin Wrote:  
(10-13-2023 03:23 PM)wb.c Wrote:  Most of the graphing models are not permitted on standard tests, even through college level exams, to professional level exams like FE, PE, and the like. Unless they plan on developing a new non-graphing scientific calculator, but then why keep the same name? It is just a bad move, happens all the time, companies make mistakes. As most have concluded, as far as Casio is concerned, the FX-991EX and similar models are the way to go. As for me, as an engineer, there are better choices for calculators, which use is now really limited to exams. I do all my calculations using SMath Studio, similar to MathCAD. And perhaps this is why Casio is focusing on middle school math, rather than advanced engineering. There was a day when a calculator was an essential tool for everyday science and engineering, now its just for exams.

As far as the name (model number) is concerned, there is a certain logic to Casio keeping the "115" or "991" in the name of any new non-graphing model in this category.

"Casio - The NCEES approves all fx-115 and fx-991 models for use on its exams. Their policy states that “any Casio calculator must have ‘fx-115 ‘ or ‘fx-991’ in its model name.”"
https://fundamentalsofengineering.com/fe...ators.html


Cases in point: the ES versions of the 115 and 991 have been reincarnated as 2nd editions. So it looks like the function set of each seems to be accepted and sanctioned as standard choices for schools.
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10-16-2023, 03:35 PM
Post: #104
RE: CASIO fx-991CW
(06-02-2023 01:47 PM)jonmoore Wrote:  And even then, the market will become flooded with all the EX's that were sold directly into education only to spend those intervening decades in dusty basements.


Just for information: In Germany, the prices new from dealer for the FX-991 DE X have doubled in the meantime (about 45 € to over 60 €).
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03-07-2024, 11:41 AM
Post: #105
RE: CASIO fx-991CW
Did you notice that when entering a number in scientific notation the calculator separates the mantissa and ten to the power of n?

Try 1 / 2x10^3 to get the wrong answer 500. ( 1 divided by 2000).

Type 1, division function, 2 then the x10 button at the bottom, 3, EXE.

The 991 EX gives the correct answer. So do my HPs ... . This upgrade is complete nonsense.
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03-10-2024, 05:50 AM
Post: #106
RE: CASIO fx-991CW
Not a bug…It’s a matter of precedence. The answer is correct if you enter 1/(2*10^3). As you entered it, the calculator calculated 1/2, and multiplies it by 10^3. You could also get the answer you desire by using the fraction template.
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03-10-2024, 01:29 PM
Post: #107
RE: CASIO fx-991CW
(03-07-2024 11:41 AM)patrick-r Wrote:  Did you notice that when entering a number in scientific notation the calculator separates the mantissa and ten to the power of n?

Try 1 / 2x10^3 to get the wrong answer 500. ( 1 divided by 2000).

Type 1, division function, 2 then the x10 button at the bottom, 3, EXE.

The 991 EX gives the correct answer. So do my HPs ... . This upgrade is complete nonsense.


(03-10-2024 05:50 AM)lrdheat Wrote:  Not a bug…It’s a matter of precedence. The answer is correct if you enter 1/(2*10^3). As you entered it, the calculator calculated 1/2, and multiplies it by 10^3. You could also get the answer you desire by using the fraction template.

It may be "by design" but it operates differently than almost any other scientific calculator made in the past 50 years. IMHO This change in operation was unnecessary and foolish.
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03-10-2024, 02:28 PM
Post: #108
RE: CASIO fx-991CW
The TI-30XS MultiView™ scientific calculator also has this "feature", according to its guidebook. I presume this is because teachers have asked for it, although I can't imagine why they would. Perhaps maths teachers don't like having an exception to the left-to-right evaluation rule for multiplication and division. It is likely that maths departments in a school will specify the calculators that students should use, and other departments just have to go along with it.

Nigel (UK)
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03-10-2024, 03:04 PM
Post: #109
RE: CASIO fx-991CW
(03-10-2024 05:50 AM)lrdheat Wrote:  Not a bug…It’s a matter of precedence. The answer is correct if you enter 1/(2*10^3).

2 [×⒑^] 3 was just a "nicer" looking 2E3, *without* any operators.
No operators, no operator precedence to speak of.

But, say it is the same as using [×] [^] keys individually. (it is not)
What is 2 [×⒑^] 3 [^] 4 ?      

2 × 10^81 ?
2 × 10^12 ?
16 × 10^12 ?
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03-10-2024, 03:58 PM (This post was last modified: 03-10-2024 04:13 PM by Matt Agajanian.)
Post: #110
RE: CASIO fx-991CW
(03-07-2024 11:41 AM)patrick-r Wrote:  Did you notice that when entering a number in scientific notation the calculator separates the mantissa and ten to the power of n?

Try 1 / 2x10^3 to get the wrong answer 500. ( 1 divided by 2000).

Type 1, division function, 2 then the x10 button at the bottom, 3, EXE.

The 991 EX gives the correct answer. So do my HPs ... . This upgrade is complete nonsense.

For the CW, as illustrated in another thread I posted, I came up with a bit of a workaround.


Here’s the gist: place the value in parentheses. For example, log 19E5 / e^2E20 should be entered as log ( 19 [x10^x] 5 ) / e^ ( 2 [*10^x] 20 ) EXE
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