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Google's Math Puzzle
Posted by
CmdrTaco
on Thu Sep 16, 2004 09:29 AM
from the weeding-out-us-regular-folk dept.
from the weeding-out-us-regular-folk dept.
An anonymous reader writes "Commuters in Cambridge, Mass., are scratching their heads over signs challenging passers-by to solve a complicated math problem. The mysterious banners are actually a job-recruiting pitch from Google."
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I'm a Reebok Sales Engineer! (Score:5, Funny)
Job as a Google engineer, sheesh. What a load of crap! Would you like whitener or a pair of extra soft socks with your shoes? Perhaps a Nuggets jersey?
Are you trolling? (Score:5, Funny)
That's not resolving and I think I know why...
Jenny, I got your number
I need to make you mine
Jenny, don't change your number
8675309 (8675309)
8675309 (8675309)
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Re:Stewie (Score:5, Funny)
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Re:I'm a Reebok Sales Engineer! (Score:5, Funny)
you are lying!
1828675309 is not prime - it is equal to 37 * 49423657.
And they said I was wasting my time learning the 37 times table up that far...
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not that complicated (Score:4, Informative)
Re:not that complicated (Score:5, Funny)
Then they're gonna wonder where all the applications are.
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Not at all -- they want the slashdotters too (Score:5, Funny)
Those of us who googled it or read the
Welcome aboard, manager!
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Re:not that complicated (Score:5, Funny)
Yes, that is, until somebody posted your link on Slashdot...
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Re:not that complicated (Score:5, Funny)
Well done, you have successfully increased the noise to signal ratio!
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Re:not that complicated (Score:5, Insightful)
Sounds reasonable and gets them good exposure at the same time. There is a reason why Google is a household name. This is one more example.
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Re:not that complicated (Score:5, Interesting)
This one is actually quite easy. We look for a particular host name in Google's address space. So let's try:
Hmm, no luck. What about the /16?
Well, we have a candidate, and it is indeed the correct one.
Once you have that domain name, you can search for more information [google.com].
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Re:not that complicated (Score:5, Informative)
That's a much more efficient search strategy. Just what they're after, methinks.
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Re:not that complicated (Score:5, Insightful)
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Re:not that complicated (Score:5, Insightful)
You don't need to know that. Here's how I solved it when I first heard about it [perl.org] in July.
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Re:not that complicated (Score:5, Interesting)
A physics teacher gives each student a barometer, and tells them that using only the barometer and brief visits to the town's tallest building, they have to determine the height of the building. Grades would be awarded based on the most creative solution.
One student started at the top, took a reading, moved to the ground floor, took a reading, and then based on that information and the barometric pressure that day, determined the approximate height of the building.
Other students basically copied the first, although with different variations (bottom to top, etc)
The student who received the only A? He went to the basement. Found the building engineer's office. Knocked on the door. Told the guy who answered, "I have a fine barometer. If you tell me exactly how tall this building is, it's yours."
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Re:not that complicated (Score:5, Interesting)
Sir Ernest Rutherford, President of the Royal Academy, and recipient of the Nobel Prize in Physics, related the following story:
Some time ago I received a call from a colleague. He was about to give a student a zero for his answer to a physics question, while the student claimed a perfect score. The instructor and the student agreed to an impartial arbiter, and I was selected.
I read the examination question: "Show how it is possible to determine the height of a tall building with the aid of a barometer."
The student had answered: "Take the barometer to the top of the building, attach a long rope to it, lower it to the street, and then bring it up, measuring the length of the rope. The length of the rope is the height of the building."
The student really had a strong case for full credit since he had really answered the question completely and correctly! On the other hand, if full credit were given, it could well contribute to a high grade in his physics course and certify competence in physics, but the answer did not confirm this.
I suggested that the student have another try. I gave the student six minutes to answer the question with the warning that the answer should show some knowledge of physics. At the end of five minutes, he hadn't written anything. I asked if he wished to give up, but he said he had many answers to this problem; he was just thinking of the best one. I excused myself for interrupting him and asked him to please go on in the next minute, he dashed off his answer, which read:
"Take the barometer to the top of the building and lean over the edge of the roof. Drop the barometer, timing its fall with a stopwatch. Then, using the formula x=0.5*a*t^2, calculate the height of the building."
At this point, I asked my colleague if he would give up. He conceded, and gave the student almost full credit. While leaving my colleague's office, I recalled that the student had said that he had other answers to the problem, so I asked him what they were.
"Well," said the student, "there are many ways of getting the height of a tall building with the aid of a barometer. For example, you could take the barometer out on a sunny day and measure the height of the barometer, the length of its shadow, and the length of the shadow of the building, and by the use of simple proportion, determine the height of the building."
"Fine," I said, "and others?"
"Yes," said the student, "there is a very basic measurement method you will like. In this method, you take the barometer and begin to walk up the stairs. As you climb the stairs, you mark off the length of the barometer along the wall. You then count the number of marks, and this will give you the height of the building in barometer units. A very direct method."
"Of course. If you want a more sophisticated method, you can tie the barometer to the end of a string, swing it as a pendulum, and determine the value of g [gravity] at the street level and at the top of the building. From the difference between the two values of g, the height of the building, in principle, can be calculated."
"On this same tack, you could take the barometer to the top of the building, attach a long rope to it, lower it to just above the street, and then swing it as a pendulum. You could then calculate the height of the building by the period of the precession."
"Finally," he concluded, "there are many other ways of solving the problem. Probably the best," he said, "is to take the barometer to the basement and knock on the superintendent's door. When the superintendent answers, you speak to him as follows: 'Mr. Superintendent, here is a fine barometer. If you will tell me the height of the building, I will give you this barometer.'"
At this point, I asked the student if he really did not know the c
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Re:not that complicated (Score:5, Funny)
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Re:not that complicated (Score:5, Funny)
ROFL. Somebody please mod parent up. That's so funny.
Never use a $4 calculator when you can use a $1600 software package instead (and then make an invalid conclusion because it rounded off for you!).
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Welcome aboard! (Score:5, Funny)
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Re:not that complicated (Score:5, Funny)
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Re:not that complicated (Score:5, Insightful)
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Re:not that complicated (Score:5, Interesting)
there is no function to it.
The variable in f(x) as f(1), f(2) is the x position of a ten digit number that sums to be 49.
With a tiny perl program it turns to be: 5966290435
This is in position 128 in the exp(1) number.
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Dangerous? (Score:4, Funny)
More details on Google's Blog (Score:5, Informative)
Monday, July 12, 2004 Warning: We Brake For Number Theory
If any Silicon Valley drivers have found that traffic is moving more slowly than usual these days on the southbound 101 right around Ralston, you may have us to blame. Last week we unveiled a billboard that's a bit unusual in that it promotes Google only to one very narrow constituency: engineers who are geeky enough to be annoyed at the very existence of a math problem they haven't solved, and smart enough to rectify the situation.
Google Billboard
In other words, the billboard (which offers problem-solvers the URL to, sorry, a page containing an even harder problem), is a recruiting campaign. We've always worked hard to hire the smartest engineers we can find, and we thought this would be a cool way to find a few more. Perhaps including you. If you're a math or computer whiz who doesn't happen to live within shouting distance of Palo Alto -- good luck, and we're looking forward to hearing from you.
- A. Googler
Been done before. (Score:5, Informative)
Frustrating (Score:5, Interesting)
A hint for those who want it...
If you're searching through all of your number theory memories and reference texts for a solution, you've left the solution far behind.
Of course... (Score:5, Funny)
7427466391 [7427466391.com]
Now, is that a better or worse answer than figuring it out yourself?
Re:aaah (Score:5, Informative)
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Re:aaah (Score:5, Insightful)
The set of functions is uncountably infinite. There are uncountably infinite functions that have f of 1, 2, 3, and 4 set to the values Google gave. The reality is that mathematically speaking, giving four numbers results in exactly no constraint on the next number; you might as well just pick one at random. "Polynomial interpolation" is one reasonable path to this, but remember that functions need not even be continuous and are ultimately just infinite look-up tables. (Note the final "solution" is just a lookup table-type function.)
To counter the obvious next objection ("well obviously it is going to be a human-meaningful number"), I take my objection one meta. Obviously we're not truly drawing from that infinite set of functions. However, there's still an effectively infinite set of "human meaningful functions", too. So the true challenge becomes not a math problem, but in sheer guessing which exact constraints the puzzle writer chose.
This is not a mathematical problem. It tries to pretend to be one, but it is not. Generally, once you know the constraints the solution is trivial.
The correct mathematical answer to all such sequences remains "The next number is whatever the hell it feels like being". I have better things to do with my time then try to second-guess somebody pretending to be clever and plucking some random thing out of the uncountably infinite set and demanding that I guess it. Thus, I don't do these puzzles; they're sophmoric in the literal sense of the term, created by people who think they are clever but don't seem to have a deep understanding of math.
People who "solve" the puzzle may impress Google, but I am not impressed by Google using this as a puzzle.
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I'm a Cheater (Score:5, Informative)
I'm a bit of a maths dunce but (Score:5, Interesting)
In case you're wondering -- or forgot -- e is the base of the natural system of logarithms, having a numerical value of about 2.71828 (though the number goes on forever).
Get file with copy of prime numbers. Get file with copy of largest precision of e. Use perl to scan for all 10 digit primes and then look for the first one in e.
Profit
or am I missing something?
Re:I'm a bit of a maths dunce but (Score:5, Funny)
yes, the answer...
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Interesting (Score:5, Interesting)
Just Google for the answer! (Score:5, Insightful)
Re:Just Google for the answer! (Score:4, Interesting)
> search engine.
You never had to "know" anything, it's just that it was easier/cheaper/quicker to know something, or employ someone who knew, than it was to look it up. This is increasingly no longer true.
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E A S Y (Score:5, Interesting)
Use Google to find the solution to Google's puzzle. [google.com]
Guess they just want people who know how to use a search engine. :)
Hmmm. I went to 42.com... (Score:5, Funny)
Re:Hmmm. I went to 42.com... (Score:5, Funny)
Maybe you're just asking the wrong question... ;-)
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SPOILERS.. (Score:5, Informative)
I won't post the URL, but here's what it says in case you want a jump on the second question;
Unfortunatley, the fun ends here. When you enter the correct password, you are taken to google lab's hiring page which I presume is accessible without jumping through hoops.
Really really lame (Score:5, Insightful)
It was really annoying. It didn't make me want to work there at all. It was like a "oh we're so smart mensa+masturbating club".
Spoiler......... (Score:5, Informative)
Why? Isn't there enough road rage already? (Score:5, Funny)
Honking at each other.
Bitching on their cell phones about their wives while pissing off the person(s) behind them who are also on their cell phones bitching about the guy that is jabbering on his phone and not moving forward with traffic.
Bumping each other and causing just enough damage to their cars to NOT really want to risk an insurance claim but also enough to want to get it fixed before the neighbors think they drive a shitty car.
Flipping over and killing each other because one of them thought that he/she had to get to work about 30mph faster than everyone else, because that one person has a much busier day of meetings than everyone else on the highway.
Enter Google -- further frustrating drivers with friggin' math problems on billboards. What? You don't think people will look at them enough to be distracted and frustrated at learning that they're not really Google material?
I call bullshit. 'cause that bitch on the uncontested divorce for $299 billboard torments me every day. Not because I don't like my marriage or want a divorce. No -- she begs the question -- "Can you beat me in court if you want the dog and the 50" plasma TV? Eh, buddy?"
Fuck you lady. Fuck you and your uncontested divorce. And fuck Google for teasing me with a job that I probably will have never known existed if it weren't for people that are actually qualified to answer the math problem having posted the g'damned answers here and made feel stupid as shit.
I'd complain more, but this guy behind me in his gas guzzling SUV is honking at me to move forward one car length while we drive past an accident. Thank god for WiFi in the car. If he honks again, I'm threatening him with the Airsoft 9mm I have in the glove compartment.
IronChefMorimoto
The Answer... (Score:5, Informative)
First, find the first 1, 3, 7, or 9 after the first ten digits after the decimal. Take the preceding 9 digits, and run it through a Prime Number Checker. [uiuc.edu] (The algorithm is in the source).
Really, the hardest part is determining the farthest decimal points of e. Here's the formula: limn->infinity (1 + 1/n)n.
It's lazy, impatient, and full of hubris! BTW, I get a finder's fee.
SCO's new hiring ad... (Score:5, Funny)
1. Sue IBM
2. ???
3. Profit!
If you have the answer to #2, please contact Darl McBride at SCO.com. We have an immediate opening for someone who can solve this riddle.
Google GLAT ( Google Labs Aptitude Test ) (Score:5, Interesting)
A few sample questions from it:
#2 Write a haiku describing possible methods for predicting search traffic seasonality.
#4 You are in a maze of twisty little passages, all alike. There is a dusty laptop here with a weak wireless connection. There are dull, lifeless gnomes strolling about. What dost thou do?
A) Wander aimlessly, bumping into obstacles until you are eaten by a grue.
B) Use the laptop as a digging device to tunnel to the next level.
C) Play MPoRPG until the battery dies along with your hopes.
D) Use the computer to map the nodes of the maze and discover an exit path.
E) Email your resume to Google, tell the lead gnome you quit and find yourself in a whole different world.
#9 This space left intentionally blank. Please fill it with something that improves upon emptiness.
#17 Consider a function which, for a given whole number n, returns the number of ones required when writing out all numbers between 0 and n. For example, f(13)=6. Notice that f(1)=1. What is the next largest n such that f(n)=n?
#20 What number comes next in the sequence: 10, 9, 60, 90, 70, 66, ?
A) 96
B) 1 followed by 100 zeros ( a Googol )
C) Either of the above
D) None of the above
#21 In 29 words or fewer, describe what you would strive to accomplish if you worked at Google Labs.
One-liner Mathematica solution to billboard puzzle (Score:5, Informative)
en = N[\[ExponentialE], 1000]; Table[x = (Floor[en*(10^k)*10^10] - Floor[en*(
10^k)]*10^10); If[PrimeQ[x], {k, x}, {k, 0}], {k, 0, 100}]
I see their strategy... (Score:4, Funny)
Re:The Answer (Score:5, Interesting)
Anyway, I guess I wasn't paying that close of attention during the IPO thing -
From the Wikipedia article: "In the IPO filing for Google, Inc., in 2004, rather than a typical round-number amount of money, the company announced its intention to raise $2,718,281,828, which is, of course, e billion dollars to the nearest integer."
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Re:I wonder (Score:5, Insightful)
Given a Billboard where the only content is a text string '{first 10 digit prime in e}.com' there are three ways to find out that it is a 'google' ad.
1. Solve the puzzle.
2. Bribe the billboard owner. (surely you have seen this billboard advertizing itsel out at one time or another.)
3. Wait till the news breaks that it is a Google Job offer.
Something tells me that Google is more interested in people who quickly solve #1, vs people who can handle #2, or wait for #3.
-Rusty
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Re:Make it hard next time... (Score:5, Funny)
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