5+5+5-5+5+5-5+5*0=

Discussion in 'Community Discussion' started by Mac'nCheese, Nov 9, 2011.

?

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

4.9%

29.2%

0.8%

65.2%
1. Mac'nCheese macrumors 68040

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#1

What does 5+5+5-5+5+5-5+5*0=

20, 0, 40 or 15?

2. szolr macrumors 6502

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#2
Er... 15?

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Feb 19, 2011
#3
Did anyone else read that as all addition the first time they saw it? @_@

Anyway, I'd assume 15.

4. GoCubsGo macrumors Nehalem

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#4
15 I think. Most will say 0 because of the multiplication by zero but I think it goes:
5+5+5-5+5+5-5+(5*0)= and that is 15.

5. szolr macrumors 6502

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#5
BIDMAS-standard maths principles lol

6. wwooden macrumors 68000

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8. dukebound85 macrumors P6

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9. iBlue macrumors Core

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10. iJohnHenry macrumors P6

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#10
"What do you want it to equal?" - Sleazy Accountant

11. cantthinkofone macrumors 65816

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#11
Hate order of operations, gets me every time.

12. jav6454 macrumors P6

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13. eawmp1 macrumors 601

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#13
I knew the meaning, but now I see the math behind it. Cool.

14. Nov 9, 2011
Last edited: Nov 9, 2011

puma1552 macrumors 603

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#14
-5

5+5+5-5+5+5-5+5*0

PMDAS order of operations, Parentheses, Multiplication, Division, Addition, Subtraction

Grouping terms according to order of operations reduces to

(5+5+5)-(5+5+5)-[5+(5*0)]
=15-15-5+0
=-5

Probably wrong, and probably another one of these useless puzzles where everyone is wrong usually on accounta the way it's entered into the computer in type format and not common sense format...pretty sure the last time one of these came up the guy did a bogus job of entering it into the computer

Or, alternatively,

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

But that is arbitrary term grouping where you are selecting which operation signs to put in or outside of the parentheses, which is no good.

15. wpotere Guest

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Oct 7, 2010
#15
Dang it... It is 15 but I have already voted.

16. iJohnHenry macrumors P6

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#16
And now you know why macaroni & cheese made it a public poll.

17. Rodimus Prime macrumors G4

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#17
Damn delexia after I put my vote in I saw I was reading one of the 5 twice and was getting it crossed. It should be 15.

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Jul 11, 2003
19. eawmp1 macrumors 601

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#19
Wrong, because YOU put in parentheses.
And multiplication=division and addition=subtraction...neither is done first. You do these from left to right.

20. dukebound85 macrumors P6

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#20
That is incorrect. You do not put () in at all in this case as () fundamentally changes the oder of operations. Addition and Subtraction are the same. Neither takes precedence over the other. Same with Mult and Division. As such, you merely go Left to Right with those operations

The reason addition and subtraction are the same is because adding -5 is the same as subtracting 5 for instance. Same logic for mult and division

21. mscriv macrumors 601

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#21
I voted 15 because that makes sense using PEMDAS and working left to right. Does left to right come into play with calculations? I don't know, grade school math was so long ago. However, puma1552's post below makes sense as well depending upon how you apply PEMDAS if it's not left to right. I don't remember the rule.

22. puma1552 macrumors 603

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#22
Thanks duke, been a long time...had I seen it scribbled on paper I would've went left to right, but since it's on the computer you always assume it's a setup/trick and not as easy as it would otherwise look.

23. waloshin macrumors 68040

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24. Nov 9, 2011
Last edited by a moderator: Nov 9, 2011

eawmp1 macrumors 601

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#24
That's why the LAST 5 zeroes out, not everything before the "+"

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