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Google's Math Puzzle
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."
I spent two days on the second puzzle (the number from e just leads you to a site with the real puzzle), only to realize that the answer was far, far simpler than I had been looking for. I think buildings two blocks down heard the "Doh!" ;-)
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.
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?
---
We spoke for about a half an hour. I don't recall a thing we said. - Colorblind James Experience
Personally, I like this approach. Maybe the problem isn't extraordinarily difficult to solve, but the ad itself has a useful purpose for Google's HR department: it finds people who are willing to solve a problem whose solution is not immediately obvious without any immediate gain, other than satisfying their curiosity. That has to be a nice plus for Google. They can limit their hiring process to those individuals and from there give them more challenging problems, take them through the interview process, etc.
Live free or die
Use Google to find the solution to Google's puzzle.
Guess they just want people who know how to use a search engine. :)
I saw this on Google Blog a few weeks ago and decided to try it out. Like nearly every problem I encounter, I also check Google for a solution and came up with it right quick. So I'm a little surprised it took so long to make it onto Slashdot.
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."
Google sucks ass anyway (not the search engine, working for the company). If you don't want to move to Mt. View California about the only jobs available at their data centers all over America are hardware managers (ooh - order replacement ide drives...) and data center techs. Google is screwing the hell out the data center techs, luring people into quitting stable jobs for a chance to get in the door at Google - using "contract positions" to build the data centers while leading people into thinking they'll get hired on and can climb their ladder to a sys admin position. If you don't believe, me do a quick monster.com search. Guess what happens when the data centers are built and the techies contracts are up... "Don't do evil" my ass.
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.
> Remember kids, you don't have to KNOW anything any more. This is the age of the
> 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.
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.
You get 466453 if you type google on a phone keypad.
I recently got a new cell phone. I took information for a search and asked for a vanity number. Then I kept hearing the numbers as they told me what was available, checking it and telling them 'no.' Finally on the 11th try I got an acceptible number. What I was searching for was a 7 digit prime. Fortunately the number with area code was the product of two primes as well. Now I can give out either the ordinal index of the prime for the local, or the prime factors of the 10 digit number. People who are unable to deal with the math just can't call me!
"Can there be a Klein bottle that is an efficient and effective beer pitcher?"
On a side note, someone was very clever over at Cingular.com. The URL 8675309.com redirects you to Cingular's web site. I'm sure that only a small percentage of people have tried that URL but I'm sure that means that hundreds or thousands of people were redirected.
Someone was definitely thinking when they set that up.
Sapere aude!
Here's a supposedly true story I heard in some class years ago - probably dynamics or physics or organic or something...
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."
-- "In order to have power, I must be taken seriously." -Mojo Jojo
The sum to all digits turns to be 49.
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.
I'm curious what sort of person can do this
I'm not the original poster but I did solve the puzzles this afternoon without "cheating". I'm a psychology/philosophy major that hasn't seen a math book in 10 years and I was able to figure it out. What I find interesting is that the answer to the first question (at least how I solved it) was an indirect hint at how to solve the second puzzle. Good luck, it was fun to work through it.
Speak truth to power.
this story has been around a long, long time -- i heard it first in AP Chem in high school. google for it, but the "traditional" text generally credits neils bohr as being the student :
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
filter: +3. Hey, look! all the trolls went away!