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5 + 5 + 5 - 5 + 5 + 5 - 5 + 5 x 0 = ?


  • Total voters
    264
I don't know what's worse - people getting the answer wrong or people getting the answer wrong and then arguing for a change in the rules of mathematics so they are right!
The answer's clearly 15 if you follow the established rules of mathematics: The rules are there to ensure consistency and if you follow them you get 15 :)
 
It's 15

PEMDAS (Parenthesis, Exponents, Multiply,Divide,Add,Subtract)

Then Left to Right

Don't believe me? Type it in the google search box and see what it returns.

Should have figured Google could do math too:

5 + 5 + 5 - 5 + 5 + 5 - 5 + (5 x 0) = 15
 
Pink∆Floyd;13828869 said:
Add a parenthesis next time :rolleyes:
^^^ Yes. With no parenthesis in the original stated equation, what keeps it from being this?

(5+5+5-5+5+5-5+5)X0= or anything else? Rules say do the parenthesis first, but where are they? Is there a rule for that when they aren't given?

Dale
 
parenthesis first, then exponents, then multiplication and division. You don't need parenthesis.


^^^ Yes. With no parenthesis in the original stated equation, what keeps it from being this?

(5+5+5-5+5+5-5+5)X0= or anything else? Rules say do the parenthesis first, but where are they? Is there a rule for that when they aren't given?

Dale
 
I am serious. And it's not arbitrary - I'm not kidding about being a literalist either - IOW's if there should be a parenthesis then it should be there. I see the idea that if a parenthesis is not there you still can
perform the operation as if it was there based on a rule to be arbitrary unto itself.

The idea that you follow PEMDAS excludes people who don't know the operational rule - and adds to the confusion of solving a basic calculation.
As it is there we now have a thread with 300 people posting 5 different answers. if the 'P' of PEMDAS was mandatory to compute a operation the
answer would be simple and a moot point.

As for the rest of the mnemonic device used - it is not arbitrary IMO.


"I would like the idea to change so that the basic operations are definite and written down". and :"The idea that you follow PEMDAS excludes people who don't know the operational rule" are the funniest lines I've every read from someone who claims to be serious. The basic rules are definite and written down. There in every single basic math book in the world. And the second line is brilliant. We can't follow rules because some people don't know them? fantastic. I guess we can throw out spelling rules too since so many people I know are bad spellers and having rules excludes them from following the rules that they forgot.
 
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While your intentions may be good, you are applying additional rules as to parentheses placement. Your logic could ultimately make the above equation:

(5+(5+(5-(5+(5+(5-(5+(5*0))))))))

There are rules. They are clear.
Unfortunately many people are ignorant of the rules. Adding an additional rule will not cure ignorance.


I'm not adding a rule - I'm saying that an operation has to operate within a defined set of 'visible' parameters.

The equation couldn't be written with ambiguity - IOWs I would make it a mandatory rule to write it as such:

(5 + 5 + 5) - 5 + (5 + 5) - 5 + (5 x 0) = 15

No one here would get the wrong answer IMO. And if one's goal is to produce the correct answer then the logic makes sense.
 
...but there are rules, and since there aren't any parenthesis, you follow the rules the way they are intended.

I'm not adding a rule - I'm saying that an operation has to operate within a defined set of 'visible' parameters.

The equation couldn't be written with ambiguity - IOWs I would make it a mandatory rule to write it as such:

(5 + 5 + 5) - 5 + (5 + 5) - 5 + (5 x 0) = 15

No one here would get the wrong answer IMO. And if one's goal is to produce the correct answer then the logic makes sense.
 
I guess we can through out spelling rules too since so many people I know are bad spellers and having rules excludes them from following the rules that they forgot.

Emphasis added. Quoted for unintentional hilarity. Or extremely subtle sarcasm. Not sure which.
 
The poll is public, no?? Why?

And anyone deviating from your stated purpose for posting is rebuked, in some way.

Why not? Why wouldn't it be public? And who did I rebuke? Who deviated from any stated purpose? How does that make me impatient? What in the hell are you talking about?
 
sadly on facebook the leading answer by far is Zero.

When i saw this and the results i thought:

those who answered 15: math/science majors
those who answered 0: non-math/science majors
 
those who answered 15: math/science majors
those who answered 0: non-math/science majors

Actually, I was home-schooled and 'dropped out' at 16. But, I tested at college level in every subject since I was 10.. :)
 
Why not? Why wouldn't it be public?

Q would have to weigh in on that, with the percentage of polls that are open vs. those that are closed.

And who did I rebuke? Who deviated from any stated purpose? How does that make me impatient? What in the hell are you talking about?

Oh, maybe this post, by you??

New poll: which witty and original comeback needs to die more:

1. 42 (answering any math question or moral question like what is the meaning of life?)
2. cool story bro (just hit the thumbs down and move on)
3. any kind of face palm picture
4. write in your own here.
 
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Q would have to weigh in on that, with the percentage of poll that are open vs. those that are closed.



Oh, maybe this post, by you??

I honestly have no idea what you are upset about. I've read your posts, you seemed to give more jokey answers then honest ones and your stuck on my one tongue in cheek post? Still don't understand why I'm nosy and impatient but whatever, I give up.
 
sadly on facebook the leading answer by far is Zero.

When i saw this and the results i thought:

those who answered 15: math/science majors
those who answered 0: non-math/science majors

So, are you assuming that everyone who posts here is a college student?
 
sadly on facebook the leading answer by far is Zero.

When i saw this and the results i thought:

those who answered 15: math/science majors
those who answered 0: non-math/science majors

What I think is it's sad that 5th grade elementary school math didn't stick for most people answering the problem.
 
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