## 90% Fail to Answer This Correctly – A Deep Dive Analysis

90% fail to answer the above problem correctly. Is that a true statement? What is the correct answer anyway? This is a problem we posted on social media and this blog and MANY people hopped on the banterwagon! After 600,000+ YouTube views and 250K+ visits to our site, we realized this is a problem many people wanted to know more about.

[contentblock id=ar_top_banner_responsive]

Full disclosure: We didn’t even design this problem, yet after we became the #1 Google result and top video on YouTube for “90% fail to answer” (and 90% fail for that matter), we started to be considered an “authority” on this topic. Although we don’t claim to know the real answer, we’ve learned a great deal about this tricky little question:

We even found someone was so passionate about this puzzle that they complained about a radio station who posted the problem…and referenced our video: https://www.scamguard.com/wave-105-radio/

Oops, we’re certainly sorry for upsetting or offending anyone! This post is designed to clarify this puzzle and get all of the facts out there for you to make your own decision. Or ignore the puzzle completely.

**Should you invest in Stocks or Real Estate?
**The nose dives we’ve been experiencing in the stock market should have been a HUGE wake-up call to anyone comfortable with stocks.

#### The Wrong Answers

First, let’s get the wrong answers out of the way. If you don’t understand order of operations (or are just a bit mixed up), you’re likely to think the answer is 1. Although that is incorrect, here is how most people see it:

(1+1+1+1+1+1+1+1+1+1+1+1)x0+1 = 1

The thought here is that everything before the 0 is eliminated, leaving only 1 left. This is a failure to understand “PEMDAS” which stands for Parenthesis, Exponents, Multiplication, Division, Addition, Subtraction. (Yes, we know about BODMAS for you non-US visitors.) Don’t worry about semantics here. No matter which part of the world you are from, it makes NO difference in this particular problem! For this instance, all we need to worry about is M and A, Multiplication and Addition. Multiply first and add second, and you are on your way to success!

[contentblock id=mid_banner_responsive]

**…or are you??**

The second common answer is 12, which might mean you have a solid understanding of math, but just missed the fact that there aren’t any + signs after each row! This is not going to work…wait a minute, now this is just getting plain tricky. Not fair guys!

Now, there is more than meets the eye with this little puzzle. Which strategy do you follow? Your head must be spinning by now. Well if you watched the video we put up on YouTube or if you’ve been by here before, you’ll know we originally went with 30. This answer was debated rather heavily and we had a few crafty little “Youtubers” translate our excitement for the answer “30!” as 30 factorial even (30x29x28…). Yes, that is the world we live in! Anyway, here’s how we came up with 30:

**The Answer…30?**

Since there aren’t any “+” signs after the first two rows, read the problem in sequential order from left to right:

1+1+1+1+11+1+1+1+11+1X0+1=?

Apply PEMDAS (or just “M” first, and “A” second) like before, and now you are looking at:

29+1×0+1 = 30

After posting the video and this blog originally, we soon discovered that this “math problem”, if you can even call it that, expands well beyond the simple answer 30, or even using PEMDAS. Other answers started flooding in, one very valid one in particular. Strong voices such as mathematicians, engineers, and other math pundits demanded that the video and article be taken down, or be changed to reflect that 2 was the real answer.

[su_animate type=”fadeInLeft” duration=”1″][contentblock id=subscribe][/su_animate]

**By the way, this is a fun diversion, however we are actually a financial technology company focused on making real estate investing easier. We achieve this by providing free investor tools, so feel free to register to the site and give them a try. We also provide how-to videos, articles, and interviews with real estate experts to help you learn how to be a great real estate investor. Looking for something solid to invest in besides stocks? We are here for you.**

#### So Maybe it’s 2?!

A comment on our initial post by user Jack Rosenfeld stated: “Having a cousin as a math teacher confirmed what I already knew. The only ‘legitimate’ equation in the problem is LINE 3. LINES 1&2 are meaningless and obviously put there to trick or confuse potential problem solvers. Nowhere in the example does it even IMPLY that all 3 lines must be used to obtain an answer, therefore the obvious solution is ‘2’, as follows 1+(1×0)+1=2. Math is simply nothing but logic and you can’t ASSUME things that aren’t stated. End of story.”

Since there are no = signs after the first two rows, and no “+” signs to connect them to the third line in the problem, all that is really relevant is “1+1×0+1=?” Perform PEMDAS, which means you work 1×0 first, and then you have 1+1, which is obviously 2. Ignore the first two lines.

So the problem ends up looking like this:

1+1+1+1+1

1+1+1+1+1

1+1×0+1=?

Simply taking 1+1×0+1 will give you 2!

What do you think? Did we cover all of the bases? Do 90% fail to answer this problem, or was that just made up? Our survey results below showed some interesting findings. Leave us a comment below and let us know what you think!

P.S. If you’re looking for more puzzles, check out our 80% Fail to Answer puzzle.

legend=”{ position: ‘top’, maxLines: 2 }”

vaxis=”{title: ‘Answer’, titleTextStyle: {color: ‘blue’}}”

haxis=”{title: ‘Percent of Answer’, titleTextStyle: {color: ‘blue’}}”]

[‘Answered the number’, ‘% of Answer’],

[‘0’, 1.8],

[‘1’, 25.2],

[‘2’, 12.3],

[‘3’, .9],

[‘4’, .1],

[‘6’, .1],

[‘7’, .1],

[‘9′, .1],

[’10’, .3],

[’11’, 2],

[’12’, 25.7],

[’13’, 3.8],

[’14’, .4],

[’15’, .1],

[’19’, .1],

[’20’, .1],

[’21’, .2],

[’25’, .1],

[’29’, .1],

[’30’, 24.4],

[’31’, 1.4],

[’32’, .2],

[’37’, .1],

[’38’, .1],

[’50’, .2],

[’55’, .1],

[’99’, .1],

[‘111’, .1],

[‘121’, .1],

[‘551’, .1],

[‘553’, .1],

[‘1000’, .1],

[/barChart]

### Happy Investing!

AssetRover Team

[contentblock id=before_you_leave]

Appreciate this post. Will try it out.

Nice read, I just passed this onto a friend who was doing some research on that. And he actually bought me lunch as I found it for him smile Thus let me rephrase that Thanks for lunch! ckefcffekdbcgcdf

Well, as a friend of mine ingenuously pointed out, the lack of operator could be read as a multiplier (like 3X or XY meaning 3 x X or X x Y) and then the answer would be 10… Which is also valid I would say.

Hi there, just became aware of your blog through Google, and found that it’s truly informative. Im gonna watch out for brussels. I will appreciate if you continue this in future. Many people will be benefited from your writing. Cheers! kedfdddfgbdkedfd

Outstanding post, you have pointed out some fantastic points, I as well think this is a very great website. eekgkceeekbbadbg

I appreciate your discussion. I do have to wonder, however, how many teachers and parents who had the opportunity to view the teaching of people…!!!

I believe the answer is truly 30 as the question on the original meme solve the following equation, which informs us definitively that the equation shown is valid.

Therefore 1+1+1+1+11+1+1+1+11 +1 × 0 +1 = 30 is really the only valid interpretation.

Solve the following equation

1+1+1+1+1

1+1+1+1+1

1+1 × 0 +1 = ?

If you want the answer to be 2 then the question is intentionally misleading because the first two lines are invalid or non equations.

The only way the can be a valid question and a valid equation is if the answer is 30.

I think I’ll go with the answer I feel is correct which is 30, but it could be 2, 12, or whatever other number you decide, at the end of the day, does it matter I think not. The one thing I’m sure/not sure of is that the makers of this Puzzle, mathematical equation, broken equation, one liner never expected so many people to spend so much of their time to discuss something that was done for fun.

I agree that the first two lines , not having a + sign after them, are not linked together nor are either of them linked to the 3rd line. Therefore the only valid line or problem is 1+1×0+1=?. Therefore 1+(1×0)+1=

1+1=2

You guys really are mathematicians! Sometimes you can LQQK so closely at a problem you complicate it up so badly you can’t see the simple solution nor agree on an answer. Why not STOP speculating, assuming, and just plain ‘ol going Rocket Scientist and go to the site posted in the “given”: http://www.bhavinionline.com? The author shows you exactly what his intention is/was. . . . 30. Mann! Go to the gym, take a walk, jog or mow the lawn . . . What have you done for the good of your country today? LOL Happy Easter! Go hunt an egg. P.S. Maybe, just maybe your version doesn’t have this info?

2. I agree that the first 2 lines are just numbers with + signs between them. They are not an equation. The only equation being asked is the 3rd line.

The answer is 552. Everything is significant in computer programming, even non-display characters like line feeds. Those must be translated some how, so here’s the computer programmer answer: all of the following computer languages yield a result of 5 5 2 regardless of how you treat the independent lines when you put the problem to the compiler.

lua language: 552

io.write(1+1+1+1+1,1+1+1+1+1,1+1*0+1)

python3 language: 552

print(1+1+1+1+1,1+1+1+1+1,1+1*0+1)

ruby language: 552

puts 1+1+1+1+1,1+1+1+1+1,1+1*0+1

javascript language: 552

console.log(1+1+1+1+1,1+1+1+1+1,1+1*0+1)

C# language: 552

using System;

class MainClass {

public static void Main (string[] args) {

Console.WriteLine (1+1+1+1+1);

Console.WriteLine (1+1+1+1+1);

Console.WriteLine (1+1*0+1)

}

}

Go language: 552

package main

import “fmt”

func main() {

fmt.Println(1+1+1+1+1,1+1+1+1+1,1+1*0+1);

}

Forth language: 552

1 1 1 1 1 + + + + 1 1 1 1 1 + + + + 1 1 0 1 + * +

QBASIC: 552

PRINT 1+1+1+1+1

PRINT 1+1+1+1+1

PRINT 1+1*0+1

Lets face it this problem is more about communication and problem solving rather than math. If this were to come across my desk, I would reach out to the person who wrote the problem and ask some questions and try to understand their intentions rather than try to calculate such a poorly written question.

To the auther of this page: I can see that you have corrected yourself.. A while back i didnt see the answer 2, so probably a lot of people emailed you or something that the answers you gave were totally wrong and i think that its pretty sad that you posted to the internet (or should i say to the people) to give the ¨right¨ answer, but in reality its totally wrong :DD well at least you have corrected yourself, soo heey everybody makes mistakes. peace

Well since I see two question marks, I will answer those:

90% fail answer? That is not a complete question so I will assume that more than 90% do answer the question (it does matter if they are right just that they answered the Question.

The second is an equation and that answer is 2( 1+1*0+1=2).

1+1+1+1+1 space/return would never mean that the next number is part of the previous number. “1+1+1+1+1” is a complete set that mean 5

1+1+1+1+1

1+1+1+1+1

1+1×0+1+1 = 12

as

5

5

2

___

12

1+1+1+1+1 space/return would never mean that the next number is part of the previous number. “1+1+1+1+1” is a complete set that means 5

1+1+1+1+1 5

1+1+1+1+1 5

1+1×0+1+1 = 12 2

_

12

THAT’S NOT HOW I SPACE THIS OUT !!!

12? Why would you add the first two lines to the last line? There is not a + between the lines. If you’re going to assume a +, why not assume a -? or a *, or a / ?

7

Sorry, messed up Omar, should have typed that as:

1 1 1 1 1

1 1 1 1 1

1 1×0 1=?

The problem is stated as:

1+1+1+1+1

1+1+1+1+1

1+1×0+1=

In eighth grade the first thing we were taught to find out was What is the question? The only question I see in this problem as written is:

1+1×0+1= There are no given parenthesis…no given anything but a sequence of addition n multiplication numbers. If you do the problem with only what is given in sequence, n stop trying to make it into some kind of complicated higher math problem out of it, it is very simple. A sixth grader could do it!

1

+1

____

2

X0

_____

0

+1

_____

1

Virginia, your reasoning is sound, but you forgot PEMDAS or BIDMAS or BODMAS. Using your reasoning though, the correct answer would be

1 + 1 x 0 + 1 = ? becomes 1 + (1×0) + 1 becomes 1 + 1 = 2. Since there are no given parenthesis or exponents or division, you do multiplication first, then left to right.

1 is the correct answer. Thank you very much

How about:

(1+1+1+1+1)(1+1+1+1+1)(1+(1*0)+1) = (5)(5)(2) = 50

If we’re going to say (1 + 1 + 1 + 1 + 1)(1 + 1 + 1 + 1 + 1)(1 + 1 x 0 + 1) = (5 * 5 * 2) = 50, we could also say (1 + 1 + 1 + 1 + 1)(1 + 1 + 1 + 1 + 1)/(1 + 1 x 0 + 1) = (5 * 5 / 2) = 12.5.

Yeah, not really… I was thinking that since it would have no sign in between the parentheses it would be implicit that the operation is multiplication. Maybe I remember it in the wrong way… what do I know?…

Well, if you’re going to add parenthesis, why not add a division sign or an exponent sign. Others think it is okay to put a + between the lines…………….js

I ‘ve seen you answer and mathematically I haven’t seen such operation of moving a line and sticking to the previous. Though we do not see a plus sign at the left of line to represent continuity there are signs indeed because the numbers are not negative. So the answer is 12. Sorry.

Interesting way to look at it Omar. I do wonder though, if I wrote:

1 1 1 1 1

1 1 1 1 1

1 1×1 1 = ?

Would the answer be 12 because you assumed all the spaces are +?

In mathematics, in order to come up with an answer, you need a question. There is no mathematical question being posed. It’s not clear why the statement has a question mark because it’s not a question, unless it is asking me if 90% fail to answer, in which case I’d have no way of knowing. In casual English, the first line is the equivalent of “[Do] 90% fail to answer?” In formal English, it makes no sense. If the question mark were not there, it still wouldn’t be saying that 90% get the answer wrong. It would be saying that 90% don’t provide an answer. But it does have a question mark so it’s not stating anything.

We do know that the first two lines each evaluate to 5. We know that the third line is the only equation and the question mark can be replaced with a 2. Regardless of whether there’s an equal sign or anything else on the first two lines, 1+1+1+1+1 and 5 are logically equivalent and are different representations of the same thing. So a matrix with 5 on line one, 5 on line two and 2 on line three is another representation of what’s shown. It’s no more of an answer than anything else because there’s still no mathematical question. So the concept of a “right” answer makes no sense.

A 1 on one line followed by a 1 on the next line is not a valid mathematical representation of the number 11, so anybody who interpreted it that way isn’t following any rules of mathematics.

It’s possible to ask many questions based on that image, and each one has a different answer. But there’s only one actual question. The question itself has nothing to do with any math problem, and a person who says that the “first” two lines can be ignored might as well ignore the “third” line too because all three lines following the question have nothing to do with the question.

So far, I’ve addressed the mathematical, philosophical and linguistic aspects of the image. What’s left is the statistical aspect. In order to answer the question, we would need data. We would need to know how many people answered and how many people didn’t answer. Knowing who didn’t answer is a logical impossibility. There’s no way to get accurate data if, by definition, those who don’t answer aren’t supplying any data. We can’t go by page hits compared to responses because any individual could reference this web page multiple times. Likewise, multiple people could read the web page concurrently.

Thus the only answer is that there’s not enough information to determine the answer and getting the data is logically impossible.

Yeah I just watched a video. They move the whole thing to one line and connect the 1s to make 11 so I get it now, but that is completely wrong, lol. If it was 11 the number as a whole would move down to a new line or a hyphen would be used to concatenate them between two lines.

Oh and there is plenty of space for more numbers on each line so if the intent is for 11 to broken between two lines there needs to be some sort of identifier to show that IE. Bold Bordered Box, hyphen, or you know actually use the whole line.

(1+1+1+1+1)(1+1+1+1+1)(1+1×0+1)

(5)(5)(2)

5x5x2

50

I am in the “2” camp, although I did not initially derive the answer as just 2. Initially, I had the matrix 5, 5, 2 and then saw that the ? appeared to only care about the third item in the matrix.

Although it might again be adding assumptions, linear algebra equations often present multiple lines of values that need to be maintained in separate locations, which leads to matrix notation. Solving a matrix can mean solving each of the lines of the matrix independently, which in this case would lead to the 1 column, 3 row matrix:

5

5

2

But you don’t even need to resort to linear algebra … just thinking of this as a segment of a spreadsheet will do.

For example, say the underlying problem was: Albert, Barry, Carmen, Dave and Ellie all have some apples, bananas and cherries. Each person has 1 apple. Each person has 1 banana. Albert and Carmen have 1 cherry each and Barry has 1 package or cherries but it has 0 cherries in it.

If we use a matrix to represent the fruit and who has them, we could get this:

Albert Barry Carmen Dave Ellie

Apples: 1 1 1 1 1

Bananas: 1 1 1 1 1

Cherries: 1 1×0 1

This is basically the same data as in the problem, only none of the addition operators are present. I represent the empty package of cherries as 1 x 0 to show that it is 1 package with 0 cherries in an attempt to convince readers who might not accept BEDMAS etc. that you do not eliminate all the other pieces of fruit just because there is an empty bag of cherries included.

If the question is “How many pieces of Fruit are there?” then the result is 12 as we just add up all the numbers in the entire matrix. But if the question is “How much of each type of fruit is there?” then we only add up the rows (5 apples, 5 bananas and 2 cherries). And indeed, if the question is “Determine the number of each type of fruit and specifically indicate the number of cherries,” we would get 5, 5, 2 as the number of each type, and specifically 2 as the number of cherries.

The problem with this “puzzle” is not the determination of a definitive answer but rather the determination of what the original creator was attempting to represent (abstractly perhaps) with the numbers. Are they a matrix? Are they a broken string that just happens to have the lines separated between the digits of each 11? Were they supposed to be added together and the creator forgot that we need an addition operator after the final terms in lines 1 and 2? Was that an intentional “gotcha”, where the creator intended the solver to be misled by the absence of operators into assuming an invalid operation (like addition) at the end of each line?

Since there are no answers to these questions at this time (and won’t be unless the creator of the puzzle comes forward and indicates the intention) we can only make our best guesses and attempt to input the fewest assumptions about how the solution should be derived. My answer is 2. I understand how 30 is reached, and concede that this might be correct as well. I can accept 12 as at least “close” and POSSIBLY what was intended if the creator made a mistake. I can even understand the reasoning behind some of the more obscure answers, like 3 (if one is presuming the answer is 30, but it too will be separated at the point between the 3 and the 0 and the ? only indicates the one available digit of the answer), or 10 (a 2 but expressed as binary, because this could be a binary equation), or 11110 (30 in binary) or 1100 (12 in binary) etc. etc. The problem is that no matter what answer is presented at least some number of assumptions are made.

One other point: the phrase “90% Fail to Answer” might actually be correct and not a grammatically awkward way of saying “90% will not get the correct answer”. Instead, if the creator of this puzzle was so sharp as to present a puzzle with so much ambiguity that it would bother the very smart cookies that can fathom the full repercussions of the potential errors or possible assumptions involved in concocting an answer, then perhaps the author did in fact mean that 90% of people will not even bother to try to answer this puzzle, as there are only 10% who are obsessed enough to debate the full ramifications of each way the puzzle can be solved.

“90% Fail to Answer” because only 10% are willing to even try.

Cheers!

Due to pagination the matrix looks wrong … it was intended to look like it might in a spreadsheet. Perhaps this will be better:

_________ Albert __Barry Carmen _Dave ____Ellie

Apples: ______1 ______1 ______1 ______1 ______1

Bananas: ____1 ______1 ______1 ______1 ______1

Cherries: ____1 ____1×0 ______1

Also it was supposed to read “package OF cherries” not “or”.

Cheers!

Wow Dave, that blew me away! That was a very thoughtful comment and synopsis…thank you for sharing some more possibilities on “solving” this strange puzzle.

The answer can’t be 30 because of the way the question is presented.

To join the 1’s to make 11, you have to assume that there’s both a text-wrapping issue and someone willing to break a number in half.

The question tells us that’s not the case, as if it were, it would read:

“90% will fail ans

wer?”

Then it would be the same width as the first 2 lines.

It isn’t, so the answer is 5,5,2 or simply 2, since there are no equals at the end of the first 2 lines.

Boy, I say Boy, (read in best Foghorn Leghorn voice) you area genius. I would make one slight “correction” though. I’m anal like that. The statement at the top would read

90% fail to answe

r?

The problem itself uses 17 spaces per line. The “e” in answer is in the 17th space. Awesome.

I would go with 2 as the most definate answer. Any other answer would be from assuming. 2 is definate.

Another assumption. Mostly to stir the pot. As stated above the lines individually equate to

5

5

2

Now taking into fact number above another denotes division. In the case you would he to solve the individual equations as above then divide as so.

5/5/2. In that case the answer is .5 or 1/2.

What about binaries?

What about them?

1+1+1+1+1 = 00000101 = 5

1+1+1+1+1 = 00000101 = 5

1+(1×0)+1 = 00000010 = 2

If each line in this equation has a value then you can get: +5

+5

+2

_________

+12

I still do not understand why one would add the top line to the second line to the bottom line. There is no + between the lines, nor at the ends of lines 1 and 2……leads us back to the discussion on assumptions. Thanks.

I think this is a problem of presentation. It is an assumption to think the first two lines are irrelevant and just there to deceive, because the problem is presented as a whole equation to be solved. Since it is presented as a whole equation to be solved it is assumed it must be read from left to right. Since there are no signs between the top rows we assume the two 1’s form an 11 but it is nonsensical to write an 11 out that way to begin with. Again, since it is presented as a whole equation we can’t assume the last line is meant to be added on its own either just because of an = sign. But I do think the answer is given to us on the last line and it has been there the entire time… the answer is in fact ‘?’. Everyone including myself has been so busy trying to plug a number in there that we have overlooked the possibility that ? is in fact the answer as shown on the page. Since we have nothing but assumptions a definitive answer cannot exist until the one who presented it can clarify. As he/she remains ? the answer is their = ?

Thanks for the analysis, Rob. I honestly do not know who created this puzzle either, that’s why we did a deep dive analysis to explore possible answers and provide a location for people to view and debate.

I’m more along the lines of saying I think it was designed to be unanswerable and musing that the answer ? is there the entire time. With so many different takes on it and assumptions that certainly seems to be the case. Good mind-bender you guys posted. Thanks

My friend…. what I think is that the only real statement we have is that 90% fail to answer…. this mean that 10% answer the good one….. look at all reply and makes stats…. the answer that get stated 10% of the time is the good one!

I’m sorry, but I don’t agee with break 11 to two 1s in different rows. Is that allowed?

That means that the first 2 rows doesn’t mean anything. ‘1+1x’ ?? What about this? Nice to see, but also no answer on it.

The only logical is 0+1= 1.

If you completely discount the first two rows, which I personally do, the only logical answer is 2 because you multiply before you add. so 1 + (1×0) + 1 = 2

In Maths equations cannot be broken into separate lines and to be on a separate line it would indicate a space so when there is a space between two numbers in Maths the powering sum would be times* therefore the equation would look like the following when working it out (Including the Bodmas rule): 1+1+1+1+(1*1)+1+1+1+(1*1)+(1*0)+1= 10 The person that wrote this was trying to make it like a puzzle but clearly does not know about the rule of spaces between numbers in maths. They intended for the answer to be 30 working it out in the following way: 1+1+1+1+11+1+1+1+11+(1*0)+1= 30

I have never heard of this order of operation that states the space equals a *. Can you provide a source? I would love to be able to definitively state that that is the correct answer. Also, I would like a source for the rule that states one must assume a space with the changing of the lines as you stated. Thank you.

https://tex.stackexchange.com/questions/251821/turn-into-thin-space-for-clearer-math-spacing/

Thank you Korry. This appears to be related more to programming than mathematics though (well, programming for mathematics anyway). I scanned a few of the links and don’t see a “rule” as far as mathematics is concerned. Did I miss it? Thanks again.

Here is a better link http://physics.nist.gov/cuu/Units/checklist.html

Thanks again Korry. As you no doubt have already seen, I’ve replied to your previous comment and link. I don’t mean to be stubborn, but I’m having a hard time accepting the relevance of a physics rule to the given “problem”. Oh well. Thanks for your efforts though.

True, but you also have to consider that Physics is mathematics. They are so tied together that you can’t have one with out the other. In away every problem from 1+1 to the equation needed to measure the gravimetric pull of a star is all physics. In a sense.

They thought they were being cute/snarky and I agree they simply do not understand mathematical principles.

Once they put the equal (=) sign on the third line and state “solve it” its no longer a puzzle its an equation.

The answer to the only equation presented is “2” … the top two lines are simply meaningless expressions in this presentation. You can not restructure the lines as you see fit.

I 100% agree with Booomer. Then again, what do I know? I’ve had fun with it though, arguing all the points.

Totally agree with Boomer. It’s just a straight forward equation at the end of the day of the 3rd line. I cannot understand all the confusion and I can only laugh at all the fancy logic being trotted out.

Seems obvious the answer is:

5

5

2 = ?

Anything else is making assumptions.

While I appreciate all the “logic” of the other posters, you cannot ASSUME that the problem wraps from line 1 to line 2 to line 3 anymore than you can ASSUME there is a + operator between the two lines. If we are ASSUMING things, I can assume there is a / or an *, or even open and closed parenthesis around the top line and then the second line, or any combination of those assumptions. If you read it as it is written, only one line is an equation. If you follow the orders of operation (PEMDAS) the ONLY answer is “2”. Then again, it could just be an idiot test, which I have passed (or failed) with flying colors…

Thanks for the comment Thomas, you make some very good points!

So any time you see an equation that is longer than one line, you ignore all of it except the last line? Really?

I only see an equation with one line, the bottom line. The other two lines aren’t part of the equation and aren’t stand alone equations as they do not have an =. Is there a mathematical rule that states what one is to do with a problem written as this? One person said to put the 1’s together to make 11’s. Another person said that you are supposed to multiply the 1’s at the end and beginning of line 1 and 2 / 2 and 3. I joined this discussion to see if anyone knows the true answer, not to be insulted or looked down on.

Many mathematical equations (and/or answers – think of the infinity numbers of PI) do no fit on a single line on a piece of paper or a single blackboard. It is perfectly acceptable to use multiple rows of data on even multiple pieces of paper or black/white boards to express a single equation. On this basis, I agree that most mathematician will answer 30 for this problem.

Well done, please don’t be swayed by people who keep trying to say you should skip the first two lines, that is nonsensical because any incomplete equation, there is no answer for.

Math has very specific rules, it is an actual language and it is read left to right, top line to bottom line, there is no rule in math that you must have an operation or nomenclature at the end or the beginning of a return line. So the number 1 at the end of the line, followed by the number 1 at the beginning of a line becomes the number 11. You simply go from one character on the first line to the next character on the next line and keep moving along . To solve it, you must think of this problem and all math problems as if you are entering information into a computer, if done properly and exactly as written, the only answer is 30.

You can’t just arbitrarily skip the first two segments of an equation and say the last segment is the only one that makes any sense, just because the nomenclature and operations don’t match the readers expectations. You must follow the nomenclature and syntax exactly as written in any math problem.

Thanks for the comment Grade!

Sample math problem.

A man has $20 in his pocket and $5 in his hand.

He walks up to a lemonade stand and buys 2 cups of lemonade for $5.

How much was each cup?

Based on the the “Do not ignore the first part of the problem” please explain how the answer would be any different from $5/2 = $2.50.

If you answer the only question on the screen you will need not assume anything but just provide an answer; 1 + 1 x 0 + 1 = 2

No assumption on base number, no assumption of Googol, calculator used, etc etc – just arithmetic.

On a computer key board, if you are continuning the line it will move itself to the next line as an unbroken number or word. This is shown as two different numbers not as 11. Too much assuming in this equation. The 3rd line is a definate statement, 1 and 2 are not.

One Answer : 11

Multiple Answers : 2 , 12 , 30

IF this were an IQ test the correct answer would always and only be 11.

May I ask how you come up with 11?

The original image has the headline: “90% Fail to answer?”

Even if the author of this problem has a solid concept of mathematics, which I seriously doubt, he or she fails in the english department.

As the headline should be interpreted, over 90% couldn’t or wouldn’t answer this problem. The original intent of the author is clearly meant to state “90% Fail to answer CORRECTLY”.

The problem is that the way it has been posted to FB (at least the one I got) does have the continuation of the expression—the break is not a “line” break but a carry over and retains the addition sign. Y’all had your fun. Now get he word out that there is a difference between

1+1+1+1+1

+1+1+1+1+1

+1+1*0+1=

And

1+1+1+1+1

1+1+1+1+1

1+1*0+1=

Jerks

I usually enjoy these kinds of problems, I often design computation algorithms and the first rule is to break the problem down, separate out the concrete facts, and list all of the assumptions. In no way could one achieve absolute certainty given the ambiguity of the assumptions by virtue of omission.

That said, I am not a mathematician by education – I was a humanities major that went into software engineering over 30 years ago, surrounded and humbled by engineers, mathematicians, and scientists far more brilliant than myself. So, here is my HUMANITIES answer to this riddle based on three possible assumptions:

1) If the problem was submitted by a student, the student gets a failing grade for submitting an invalid problem.

2) If the problem was submitted by a teacher, fire the teacher for gross incompetence.

3) If the problem was proffered by an investment entity, run (do not walk), because that entity has proven, by omission or commission, to be incompetent, deceitful, or careless by posting an incomplete problem and, to compound matters, not correcting the actual original post long after being called on it, knowing full well the original post continues to be shared globally. It is the last part that is unforgivable.

Hi Firstlight,

That was a very well written comment and we take concerns like this very seriously. We certainly didn’t intend to deceive anyone when we shared this puzzle on Facebook originally. This puzzle as we originally found it was only an image. We posted this image on Facebook to see what people thought the answer was. The #1 goal was fun!

A lot of people were asking us what the answer was to the puzzle that we shared. We went to a number of different sources, found a likely approach to solving the problem (since no +’s were at the end of the first two rows), and thought it would be more interesting to create a video response and a post that people could stop by and check out.

Due to the surprising amount of responses we received on YouTube and Facebook, it was apparent that two very different and valid approaches to solving the problem emerged and one we did not anticipate, “2”, also formed.

We completely agree with what you are saying and humbly apologize if we have mislead anyone, showed incompetency, deceit, or carelessness by sharing this puzzle that has been making its way across the internet. This answer was strictly our opinion on a method of deducing the problem. We had no intention of tricking anyone and thought the ambiguity of the problem made it fun and interesting for our subscribers, readers, viewers, and members.

Thanks for stopping by and sharing your thoughts! The real intent of the puzzle is for entertainment purposes only and if there are any particular corrections or ways that this puzzle could be more complete, we certainly value your opinion!

On a graphing calculator with multiple rows available on the screen, a math equation with multiple rows of numbers such as this one, would make all rows relevant. This gives us an answer of 30 for this given math PROBLEM.

From what I remember in elementary math: unless there are specific items included, parentheses as an example, you work math problems from left to right. Also, anything times 0 = 0. So, with that in mind, the answer is 1.

You remember basic maths incorrectly then. There is an order of operation PEMDAS or BODMAS depending on which part of the world you learnt maths in. You always complete items in parentheses first, then perform any exponentials, then multiply and divide then add and subtract so the final line is calculated as 1+ (1×0) + 1 = 2

Under the explicit instructions given there is only room for a one character answer on the third line (giving the maximum of 9 characters). The answer must be ‘3’ (ie. 30 truncated to its first digit). All those who have answered 10 or more have not read the instructions. This equation was always a mathematical problem and a spatial awareness test combined. Less than 1% of people have answered correctly.

which explicit instructions are those? I must have gotten a truncated copy of the puzzle/problem because mine didn’t come with any instructions.

According to Pemdas you would only do the multiplication first if it was in parentheses. If no parentheses you work left to right. Once you add all numbers then multiply by zero and add 1 the answer is 1.

incorrect, parentheses, exponents, multiplication, devision, adition, subtraction… No parentheses is needed to do the multiplication first, if there are parentheses you do them before multipling (1+1)*4+2=

barb pemdas just means parenthese is before multiplication ie (1+1)+3*2-5= 2+6-5=3

Incorrect. According to Pemdas, you do parenthesis, then exponants, then Multiply and divide, then add and subtract. Because parenthesis, and expnants are not present, you begin with multiplication and division.

Two interesting points

1) Why concatenating the lines makes sense. Suppose the equation used the number google (it was a number long before it was a search engine and is defined as 1 followed by 100 zeros) so google + google = ? or 10000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000+10000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000=?

In this case. we could not easily write this equation on a piece of paper in its longest form. We would have to make a decision where to allow breaks or new lines. It could happen anywhere in the middle of google so why not allow it to happen between 11?

2) The equation presumes we are working in the decimal system. But the lack of the digits 2-9 means we could be working in the binary system or the math system used by computers. In this case the answer would be 1110.

Actually, the search engine is “Google”. The mathematical number is “Googol”.

If you answer the only question on the screen you will need not assume anything but just provide an answer; 1 + 1 x 0 + 1 = 2

No assumption on base number, no assumption of Googol, etc etc.

John’s nice catch is incorrect since there is an x in between the 1 and 0 in the third line, not another +. If you go with 11s then you get 1+1+1+1+11+1+1+1+11+1×0+1= since there were 5 numbers in lines 1 and 2 but only 4 in line 3. Thus the answer in this context would be 30, not 31.