- 02-26-12 03:19 PMLike
*2* -
- Um, you are mistaken. Sorry, my previous numbers were wrong, I did 10+/-10%

No, 10% = 0.1 because 10/100=0.1

What you are looking for is 100*(110%)=110

Try on any other calculator, and you'd get the same answer02-26-12 03:31 PMLike*0* - I have tried on several actually, didn't want to make a fool of myself!

Try it on your phone, 9860 calculator agrees with me. 100 + 10 % = 110.02-26-12 03:37 PMLike*0* -

Fortunately, the calculator, which is correct, can help you with that.

"10%" when used as you did in a calculation - as a standalone number - equals 0.1, so the calculator's answers of 99.9 and 100.1 are correct.

The answers of 110 or 90 that you were expecting would be obtained by calculating 100 plus or minus 10% of 100, which you did not specificy in your calculation. In other words, 100+(10%*100)=110 and 100-(10%*100)=90.02-26-12 03:39 PMLike*5* - Good thing you are not a math teacher

Fortunately, the calculator, which is correct, can help you with that.

"10%" when used as you did in a calculation - as a standalone number - equals 0.1, so the calculator's answers of 99.9 and 100.1 are correct.

The answers of 110 or 90 that you were expecting would be obtained by calculating 100 plus or minus 10% of 100, which you did not specificy in your calculation. In other words, 100+(10%*100)=110 and 100-(10%*100)=90.

Try it on your phone.02-26-12 03:43 PMLike*0* - This is what the phone is thinking when you type 100+10%

It is thinking 100+10% (of 100, or of previous answer) = 110

Trust me on this one man, I've done Calc 3, and verified this with multiple high end calculators, including the Casio f991 and Ti-Nspire CAS02-26-12 03:49 PMLike*0* - Rgainsmi - I thought your statement of the problem was quite simply and accurately stated, and easy to understand. I have tried the exact calculation on 6 other devices in my home (just to make sure I didn't take a trip to another planet), and my PB is the only device that calculated such an unusual result.02-26-12 03:51 PMLike
*0* - Guys, please try this on a scientific calculator. All other calculators assume that 10% is of the previously inputted number. Try any graphing calculator or scientific calculator02-26-12 03:53 PMLike
*0* - this calculator does work as long as you use it correctly:

100+10%*100= 110

you gotta use the calculator the way it works, get with the program02-26-12 03:55 PMLike*0* -
- Sorry but we don't all carry a scientific calculator, we use what's on hand.

Why one calculator says one thing and one says another using the exact same keys is NOT scientific. Plain annoying!02-26-12 03:56 PMLike*0* - In lower end calculators, they lack the processing abilities, and make random assumptions. On the playbook, it does not, and I'm rather surprised it does not

If you try the scientific calculator 10E app on the blackberry phone, it will give you 100.1

The flaws in the BBOS calculator was one of the reasons why the app was created.

You weren't wrong in your calculations either in all honesty, the calculator was just dumb02-26-12 04:00 PMLike*0* - Yeah, deja vu. I guess there are a few folks that do carry around a scientific calc. But for the last I-don't-know-how-many-years, all consumer-type calcs work in accordance with Rgainsmi's expectation and RIM should fix this on the PB. The PB does have a scientific calc option and if they want, leave the true, long version math calculation there.02-26-12 04:09 PMLike
*0* -

20.0? Wrong......!!!

This as basic as fraction calculation can be... 10% = 1/10 = 0.1, even my 8 year old daughter would get that right...02-26-12 04:12 PMLike*0* -

Order of operations. In grade-school it's taught using the acronym BEDMAS. Brackets, Exponents, Division/Multiplications, Addition/Subtraction. That's the order in which you process a written math task.

So if I ask you what's 3 + 1 * 2, the correct answer is 5. You do the 1 * 2 part first, getting 2. Then you do the 3 + 2 part, resulting in 5.

Most calculators take the order that you type things in, which would give you an answer of 8, which is*wrong*. Some calculators are designed to let you enter things as a string of instructions and they will then execute the equation in the proper sequence. For bonus fun, Google "Reverse Polish Notation".

Most cheap calculators assume the operator is a clueless schleb. The percent operator (key) does what*you*think it should do; take the current displayed number and manipulate it as a faction of the previous displayed number. X + Y% means "take X, and add Y% of X to X".

The correct mathematical or engineering function of the percent operator is to simply divide the displayed number by 100, turning a number expressed as a percentage into its*correct*definition. Understand 10%*is*.10 not any other value. Similarly 37% is .37, not any other value. "100 + 10%"*is*100.10, not any other value.

The layman*means*to ask for "100 + 10% * 100" but has no clue how to express themselves. Because the vast majority of people can only dimly recall grade 4 math (because evidently anything more complicated than addition is "too hard" and "too useless") but remember which season of American Idol Clay Aitken came in 2nd place during, calculators made for the masses assume cluelessness.

End result: the Playbook's calculator assumes you know what you're doing. The other tested calculators, including the standard BB calculator assume you're about 8 years old, at least mentally.

This is only annoying because you're bumping into one of the many parts of reality that involve Knowing Something, where "Something" isn't which running-back had the most rushing pass-yard interception shots-on-goal batting-average 3-point mid-court slam-dunk penalty-minute mistresses (to include Golf).02-26-12 04:17 PMLike*12* - Yikes, folks! First of all, this has already been covered in more than one thread here on Crackberry, and hundreds of threads elsewhere regarding how a particular device handles the percent calculation.

Simply put, some calculators do this X+Y%*X= . . .

. . . while others do this X+Y%*1= (where "1" can also be "z" -- in other words, whatever number you enter to calculate a percentage of)

In a certain sense, both are "right" -- neither are "wrong." But whereas the second approach is right mathmatically, the first approach is only "right" in the sense that it is what some users expect the percent key to do for ease of use. (Although, of course, if that is the understood expectation, then the first approach does also result in the mathmatically "right" result!)

It really is just a matter of how the calculator was designed to provide you with a percent key/function. Either it assumes you are using the percent key to calculate a percent of the first number you entered (as in the first example above), or it assumes you will specify what you want to calculate the percentage of (and defaults to 1) (as in the second example).

Some people prefer their calculator to do one or the other, but, again, neither gives an incorrect result (as the OP is claiming the PB does) once you realize what the calculator is built to assume/do. Personally, I prefer the second approach, where I have to specify what I am taking the percentage of. It is also the mathmatically correct approach. Try this in Excel, entering "=100+10%" results in 100.1 as the answer. Entering "=100+10%*100" in Excel results in 110 as the answer. That is how the*math*should work.

Many people prefer the first approach, thinking that it is the easiest/best use of the percent key - getting a quick percentage of whatever first number they enter (to calculate tips in restaurants?!). I'm not putting anyone down for that preference, but it is an ease-of-use preference, and not, strictly speaking, how the math should work.

And I don't think this should be "fixed"/changed on the PB. The PB also has Sheets To Go, which calculates "=100+10%" as 100.1, which it*should*. I would not want any single device of mine to calculate the same equation in two different ways. I think RIM got this right!Last edited by ORMojo; 02-26-12 at 04:31 PM.

02-26-12 04:24 PMLike*3* - Good thing you are not a math teacher

Fortunately, the calculator, which is correct, can help you with that.

"10%" when used as you did in a calculation - as a standalone number - equals 0.1, so the calculator's answers of 99.9 and 100.1 are correct.

The answers of 110 or 90 that you were expecting would be obtained by calculating 100 plus or minus 10% of 100, which you did not specificy in your calculation. In other words, 100+(10%*100)=110 and 100-(10%*100)=90.masterscarhead1 and fanatical like this.02-26-12 04:41 PMLike*2* - 2012 Jan 24: http://forums.crackberry.com/blackbe...k-what-691535/

2011 Oct 5: http://forums.crackberry.com/blackbe...entage-657422/

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# Calculator is wrong!

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