Calculator Button Means

[drjackool]

Hi
What means equal sign and plus and mines sign in the following calculator?

In the normal calculators when calculating sums and multiples In succession the result will be incorrect, because multiple operator has higher priority than add.
I think this calculator obey this priority or those buttons means another things?

Thanks

 

[TJ Hooker]

I would guess that the + - buttons includ an equal sign because pressing them computes whatever operation was entered previously. So let's say you punch in 3 x 4. Then hit the '+=' button. It would calculate the product of 3x4 and display '12', as if you had pressed '='. Additionally, the calculator would then be ready to accept a new number to be added to the previously computed number.

That doesn't look like a scientific calculator so it probably just computes things in the order they are entered, rather than following proper order of operations.

 

[Ralston18]

Just a running total if I remember correctly.

Try 10 + 20 + 30 + 40 using the grey [+=] key between entries. You should see 10, then 30, then 60, then 100 as you proceed.

Likewise try:

100 - 10 - 20 - 30 - 40 using the red [- =] key between entries. You should see 90, then 70, then 40, then 0 as you proceed.

Then test other sequences of values including negative numbers and watch the display.

Should be easy to test and confirm that the keys are indeed just maintaining a running total as you go.

 

[Math Geek]

yup, ralston has it.

if doing a long sequence of adding and subtracting, this will display the new total as you go. this is due to not having the ability to shot multiple lines or even the string of calculations like a new calc will display for you.

 

[drjackool]

I'm confused. I currently do not have this calculator for test.
If i enter this 2x4+3x6 what is result? is 26 or 66?
I need a desktop calculator with ability to calc series of additions and multiples.
I visited the vendor web site (for CASIO DS-120TV model) but i could not found the calculator manual!

 

[TJ Hooker]

In that example it would likely (incorrectly) be 66. Like I said, it does not appear to be a scientific calculator, so it wouldn't implement order of operations, and would instead compute each operation in order as you enter them.

Just get a scientific calculator, you can get one for as little as $5. E.g. https://www.amazon.com/Texas-Instruments-Scientific-Calculator-Accents/dp/B00000JBNX/ref=sr_1_5?s=office-electronics&ie=UTF8&qid=1508788793&sr=1-5&keywords=scientific+calculators

 

[drjackool]

In the catalogue of this calculator writes "Adding Machine". in the Wikipedia "https://en.wikipedia.org/wiki/Adding_machine"
Writes modern adding machines can calculate expression like this:

To figure out this: 	               Type this on the adding machine:
2+17+5=?           	                2 + 17 + 5 + T
19-7=? 	                                 19 + 7 - T
38-24+10=? 	                         38 + 24 - 10 + T
7×6=? 	                                 7 × 6 =
18/3=? 	                                 18 ÷ 3 =
(1.99×3)+(.79×8)+(4.29×6)=? 	1.99 × 3 = + .79 × 8 = + 4.29 × 6 = + T

 

[drjackool]

In that example it would likely (incorrectly) be 66. Like I said, it does not appear to be a scientific calculator, so it wouldn't implement order of operations, and would instead compute each operation in order as you enter them.

Just get a scientific calculator, you can get one for as little as $5. E.g. https://www.amazon.com/Texas-Instruments-Scientific-Calculator-Accents/dp/B00000JBNX/ref=sr_1_5?s=office-electronics&ie=UTF8&qid=1508788793&sr=1-5&keywords=scientific+calculators

I need calculator with big display and buttons. for my job.

 

[Math Geek]

usually what you want is described as "direct algebraic logic" which means it knows order of operations and follows those rules.

there are a ton of freebie phone/tablet apps that can easily handle this. if you got a tablet you can use, grab one of those apps and then you got a nice big calc to work with

 

[drjackool]

usually what you want is described as "direct algebraic logic" which means it knows order of operations and follows those rules.

If this model support it, it is enough for me!

 

[Phillip Corcoran]

usually what you want is described as "direct algebraic logic" which means it knows order of operations and follows those rules.

If this model support it, it is enough for me!

But if you don't know how to use it fully, how can you be sure your calculation results are correct?

Buy a new one with full instructions, they don't cost a fortune.

 

[Math Geek]

+1 ^^^^^ since this is for work, i assume accuracy is important. i'd make sure what you get works with the way you want to think about it. going cheap may not be the answer for you. i'd get something with 2 lines at least so you can see exactly what you are entering before hitting =.

relying on an older single line one to keep track for you is asking for trouble.

 

[USAFRet]

I'm confused. I currently do not have this calculator for test.
If i enter this 2x4+3x6 what is result? is 26 or 66?
I need a desktop calculator with ability to calc series of additions and multiples.
I visited the vendor web site (for CASIO DS-120TV model) but i could not found the calculator manual!

If you enter it exactly in that order...

2x4 (=8)
8+3 (=11)
11x6 = 66

 

[RealBeast]

Perhaps you should stick to a pencil and paper to insure proper results, until the recent wave of poorly educated people the uniform CPA exam in the US allowed pencils and paper to insure that you could actually do manual arithmetic.

Calculators are for advanced users that can recognize obvious errors.

Just sayin'. Good luck.

 

[drjackool]

In that example it would likely (incorrectly) be 66. Like I said, it does not appear to be a scientific calculator, so it wouldn't implement order of operations, and would instead compute each operation in order as you enter them.

Just get a scientific calculator, you can get one for as little as $5. E.g. https://www.amazon.com/Texas-Instruments-Scientific-Calculator-Accents/dp/B00000JBNX/ref=sr_1_5?s=office-electronics&ie=UTF8&qid=1508788793&sr=1-5&keywords=scientific+calculators

This is not answer.

 

[drjackool]

In that example it would likely (incorrectly) be 66. Like I said, it does not appear to be a scientific calculator, so it wouldn't implement order of operations, and would instead compute each operation in order as you enter them.

Just get a scientific calculator, you can get one for as little as $5. E.g. https://www.amazon.com/Texas-Instruments-Scientific-Calculator-Accents/dp/B00000JBNX/ref=sr_1_5?s=office-electronics&ie=UTF8&qid=1508788793&sr=1-5&keywords=scientific+calculators

This is not answer. it calculator obey operation priorities.

 

[Alabalcho]

If you do calculations of any sort for work, and you rely on calculator to decide on priorities - you're in the wrong job.

The calculator on the picture has "memory function". If you learn how to use it, you'll have much less chances of an error (and a bridge collapsed, or stock takeout going wrong).

 

[drjackool]

I bought a CASIO DS-1B. Please close this thread.