Poll: Solve a simple math problem

[Urgh76]

Oh god damn it.

I missed a minus 1 among the adding so I hit 16 instead of 14

 

[t3h br0th3r]

The guy with the degree in English says the answer is zero.

Or were you supposed o use order of operations, thus making the zero only cancel out a single +1.

Screw it, I'm going to read some Ginsberg and mock your essay writing ability.

 

[Lazy Kitty]

10*1=10
10-1=9
9+5*1=14
14+0*1=14

So the answer's 14.
Multiplication has a higher priority than addition.
There are no brackets indicating the -1 or the *0 have any priority over the other things.
It's not:
1+1+1+1+1+1+1+1+1+1-(1+1+1+1+1+1+1)X0
or
(1+1+1+1+1+1+1+1+1+1-1+1+1+1+1+1+1)X0
or any other variations containing brackets.

It's more like
1+1+1+1+1+1+1+1+1+1+(-1)+1+1+1+1+1+(1X0)

 

[madwarper]

I have a textbook that said 1/0 = infinity. The textbook isn't wrong because the 0 is not actually supposed to be a 0, but a very small number. 1/(very small positive number) approaches infinity.

No, it is Wrong.

If it X = ∞^-1 (ie. approaching 0, but NOT EQUAL TO 0), then the answer of 1/X would be "approaching infinity".
However, since 0 DOES mean 0. 1/0 = undefined.

 

[drisky]

Its fourteen but its also a stupid trick question to mess up people who rush.

 

[Freakzooi]

I guess its easy to miss the fact that you must calculate the (1x0) before you actually add the 1's together (and substract 1 once too) if you don't do math problems daily. The whole 'problem' is based on people both missing the single '-' and/or not knowing or forgetting the final part of the equasion, since it's counterintuitive to not multiply everything by zero at the end because it's the final part of the string of numbers.

It's a kind of funny problem, but no need to get all worked up if some people think the answer is 0. Or 16 for that matter. If you don't do math reasonably often it's easy to forget, and certainly not a proof of general stupidity or anything.

 

[Kadoodle]

1+1+1+1+1+1+1+1+1+1-1+1+1+1+1+1+1X0=4

(1+1+1+1+1+1+1+1+1+1)-(1+1+1+1+1+1)+(1*0)
first part equals 10 (easy part)
second part equals 6 (also easy)
third part equals 0 (multiplication always goes first, math rule)

So we got 10-6+0= 4

OP: you'r poll is a bit off...

You're not supposed to group them like that...addition doesn't take priority over subtraction.

 

[thahat]

14. quite surprised so many people did not see that one 1 with a minus in front of it and such. or missed some other critical thing.

 

[Alfador_VII]

Yeah it's 14, although I can see how you would get 16, I nearly missed that minus sign in the middle

Zero seems logical, but you don't just do the operations from left to right. multiplication has priority over addition and subtraction, so that only cancels out the last 1, not the whole total.

 

[ImprovizoR]

It's 14. Not that hard you just have to be careful around that minus. I almost missed it.

1+1+1+1+1+1+1+1+1+1=10
10-1=9
9+1+1+1+1+1=14
14+1x0=14

 

[t3h br0th3r]

oh, 14.

Man i feel stupid.

 

[Randomperson9999999]

im stupid i forgot the order of operations i said 0

 

[Musiclly enhanced]

depends if your doing (1+1+1+1+1+1+1+1)x0 which is 0
or 1+1+1+1+1+1+1+1+1+1+1+1x0 which could be 0 or higher

 

[Sozac]

Dammit didnt see that -

 

[ExileNZ]

I get the impression by your edits that the answer is supposed to be zero, although to memory multiplication/division is resolved first, addition/subtraction second, which would make the answer not zero (although one less than the answer I gave for the poll, since I forgot to multiply by zero).

 

[Kenneth Blaney]

0=1-1
0=1-1+1-1
0=1-1+1-1+1-1
0=1-1+1-1+1-1+.....
0=1+(-1+1)+(-1+1)+....
0=1+0+0+0+...
0=1

Good one. The failure is in "0=1-1+1-1+1-1+..." which is actually a way of multiplying infinity and 0. This is an "indeterminate form" and so may not be strictly equal to 0.

Consider lim x-> 0 of sin(x)*1/x.

This limit is also 0*inf which can be converted to 0/0 so that we may apply L'Hopital. This brings the limit to the form lim x-> 0 of cos(x)/1 = 1.

Indeterminate forms of limits are actually the only way we can actually divide by zero.

 

[Hero in a half shell]

1+1+1+1+1+1+1+1+1+1-1+1+1+1+1+1+1x0=?
[small]And yes in this case x means multiplication.(what? I'm a lazy typer that's too unfamiliar with doing math online. Paper rocks)[/small]

To work out which bits to do first, use BEDMAS

BED Multiplication Addition Subtraction

So it's:
1+1+1+1+1+1+1+1+1+1-1+1+1+1+1+1+1x0=? multiplication comes first

1+1+1+1+1+1+1+1+1+1-1+1+1+1+1+1+(1x0)=? 1x0=0

(1+1+1+1+1+1+1+1+1+1)-(1+1+1+1+1+1)=? Then addition

(1+1+1+1+1+1+1+1+1+1)-(1+1+1+1+1+1)=? (10)-(6)=?

10-6=? Then subtraction

10-6=4

Answer=4, wait, that's not even in the poll. What's going on?

 

[Bloodstain]

Oh snap, didn't see the minus sign. The solution is 14.

 

[Raeil]

I swear, this question has been killing me on FB. 0 still has a majority there, which saddens me greatly, but at least here the possible answers (13, 14, 15, and 16) are in the majority. The reason I'm counting those is that if you miscount the 1's or don't see the subtraction symbol, you can make a trivial error.

Now, since I'm a math major, lets answer some other questions!

1) Why is it not 0? Simply put, the order of operations (Parenthesis, Exponents, Multiplication/Division, Addition/Subtraction) tells us to look for parenthesis or exponents (there are none), then do any multiplication or division from left to right (with no preference to either first), then do any addition or subtraction from left to right (with no preference for either). To simplify this problem into its operations, we have 10 - 1 + 5 + (1 * 0).

2) Dividing by 0 would make it infinity, right? Not exactly. Division by zero has been purposely left undefined by mathematicians (it is much, much simpler and effective than trying to develop a definition), so the answer to the problem would be undefined as well. Since the error has been fixed, this is no longer an issue, but infinity is an odd concept that really needs to be taught/discussed more.

3) (another infinity question) Multiplying 0 by infinity is still 0, right? Well, not really, no. This is one of the other operations which has been purposely left undefined by mathematicians. If you're trying to find a limit of a function (calculus thing), then you might be able to see how fast the equation is approaching 0 and infinity, and from there determine the limit to be one or the other. However, 0*infinity is undefined if presented as an equation.

Yay, math! I reeeeeeally need to get back to school... I'm starting to teach math on gaming forums. *facepalm*