Can you pass the Google test?

Could you get a job with Google?

There's only one way to find out.

A fabulous blog post from Tihomir Nakov records some of the questions put to a friend seeking a job with the company. (Apologies: the link is temporarily not working but you've got the gist below anyway).

Here they are:

1. How many golf balls can you fit in a school bus?

2. You are shrunk to the height of a nickel and your mass is proportionally reduced so as to maintain your original density. You are then thrown into an empty glass blender. The blades will start moving in 60 seconds. What do you do?

3. How much should you charge to wash all the windows in Seattle?

4. How would you find out if a machine’s stack grows up or down in memory?

5. Explain a database in three sentences to your eight-year-old nephew.

6. How many times a day does a clock’s hands overlap?

7. You have to get from point A to point B. You don’t know if you can get there. What would you do?

8. Imagine you have a closet full of shirts. It’s very hard to find a shirt. So what can you do to organize your shirts for easy retrieval?

9. Every man in a village of 100 married couples has cheated on his wife. Every wife in the village instantly knows when a man other than her husband has cheated, but does not know when her own husband has. The village has a law that does not allow for adultery. Any wife who can prove that her husband is unfaithful must kill him that very day. The women of the village would never disobey this law. One day, the queen of the village visits and announces that at least one husband has been unfaithful. What happens?

10. In a country in which people only want boys, every family continues to have children until they have a boy. if they have a girl, they have another child. if they have a boy, they stop. what is the proportion of boys to girls in the country?

11. If the probability of observing a car in 30 minutes on a highway is 0.95, what is the probability of observing a car in 10 minutes (assuming constant default probability)?

12. If you look at a clock and the time is 3:15, what is the angle between the hour and the minute hands? (The answer to this is not zero!)

13. Four people need to cross a rickety rope bridge to get back to their camp at night. Unfortunately, they only have one flashlight and it only has enough light left for seventeen minutes. The bridge is too dangerous to cross without a flashlight, and it’s only strong enough to support two people at any given time. Each of the campers walks at a different speed. One can cross the bridge in 1 minute, another in 2 minutes, the third in 5 minutes, and the slow poke takes 10 minutes to cross. How do the campers make it across in 17 minutes?

14. You are at a party with a friend and 10 people are present including you and the friend. your friend makes you a wager that for every person you find that has the same birthday as you, you get $1; for every person he finds that does not have the same birthday as you, he gets $2. Would you accept the wager?

15. How many piano tuners are there in the entire world?

16. You have eight balls all of the same size. 7 of them weigh the same, and one of them weighs slightly more. How can you find the ball that is heavier by using a balance and only two weighings?

17. You have five pirates, ranked from 5 to 1 in descending order. The top pirate has the right to propose how 100 gold coins should be divided among them. But the others get to vote on his plan, and if fewer than half agree with him, he gets killed. How should he allocate the gold in order to maximize his share but live to enjoy it? (Hint: One pirate ends up with 98 percent of the gold.)

One of his readers has a tilt at answering them  (scroll down to Tom).

But actually I think the answer to all the questions is easier - Google them. So, for instance, you can discover the best estimate of the number of piano tuners in the world. It is made by William Poundstone who estimates it at 20,000

Comments

[Ian Kemmish]

So this is a company staffed by people who can't find a shirt in a closet full of them? That explains a lot.

I'm a techie, but I still think none of these questions is as effective in finding a high flyer as "Explain the causes of the Seven Years War in less than 100 words."

By the way 20,000 piano tuners is way too low. Everyone who owns their own harpsichord has to learn how to tune it, and once you can do one, you can do the other. They should have asked for "commercially active" piano tuners.

[Bay]

1. A US school bus? I'm guessing 25,000.

2. Crouch down.

3. Use London - 5 million pounds

6. 11

9. nothing

12. 7.5

14. No, you'll almost certainly lose.

I've probably misunderstood what's required, and many of these are badly phrased, but there you go.

[Tony Collings]

Answer to 12 is 90 I belive and not 7.5

In my day 3:15 mean't that the big hand was on 12, and the little hand on 3. That angle would be 90 degrees.

[R DEYOUNG]

If the big hand is on the 12 and the little hand on the 3, that would be 3:00, not 3:15. I'm teaching my 2nd grader to read an analog clock. Clocks must have been a little different in your day, huh Tony? 7.5 degrees is right.

[Sachhin]

2. Surely if you crouch down, the downward pressure created by the blades would crush you, or the upward force would propel you through the blades....or maybe im being an idiot...its friday after all :p

I would stand on top of the blades and hope i am propelled out

7. Look on google Maps...it is a Google interview after all, and probably a question to see how much the candidate knows about the company products

[P Thomas]

For the second question, unscrew the blender blades and then use the blade to crack the glass. If you do a Google search for blender blade images, you will see that most can be unscrewed. If you crouch down, the suction of the moving blades will pull you into its path.

[Jim Eliason]

#12 - no, the hour hand and the minute hand are both on 3, so there are 360 degrees difference.

#16 - weigh three balls on each side. If balanced, weigh the two left to see which is heavier. If one set of three balls is heavier, take two of the three, put one on each side of the balance. If they are balanced, the one not on the scale is heavier; otherwise, you'll find the heavier on the scale.

[Andy]

Oh, come on, all you clock readers:
At 3:15 the minute hand is pointing exactly at 3 o'clock. The hour hand is at 1/4 of an hour past 3 o'clock, i.e. 1/4 of 1/12 of 360 = 7.5°
One of the fundamental rules of online life - don't let ignorance stop you from shooting your mouth off - clearly applies to Maths as well!

[Doug]

#12 - 7.5% is correct. The little hand moves 30% for each complete rotation of the big hand. At 3:00, the little hand is exactly on the 3 when the big hand is on the 12. As the big hand moves toward the 3, the little hand moves (more slowly) toward the 4. When the big hand gets 1/4 of the way around the clock to the 3, the little hand has rotated 1/4 of the way to the 4. One quarter of 30% is 7.5%.

[Neil Williamson]

12. No, really, he is right, it's 7.5. At 3:15, the hour hand points at the three, and the minute hand has moved a quarter of the way from the 3 to the 4. As such, the angle is 1/4 multiplied by 1/12 multiplied by 360. Which is 7.5

13. The 1 and 2 minute people go over together (2 minutes), then the 1 comes back with the flashlight (3 minutes). Then the 10 and the 5 go over (13 minutes) and the 2 comes back with the flashlight (15 minutes) then the 1 and the 2 cross the bridge together just in time. (17 minutes).

[John]

#12
At 3:15 the minute hand is precisely on the 3 and, since 1/4 hour has elapsed since 3, the hour hand is 1/4 of the way between the 3 and the 4.
There are twelve intervals between the twelve numbers.
There are 360 degrees around the full circle.

A Google search on (360/12)/4 yields 7.5 degrees.
Google just called and gave me the job for getting in a slick plug for Google.

[John]

#12
At 3:15 the minute hand is precisely on the 3 and, since 1/4 hour has elapsed since 3, the hour hand is 1/4 of the way between the 3 and the 4.
There are twelve intervals between the twelve numbers.
There are 360 degrees around the full circle.

A Google search on (360/12)/4 yields 7.5 degrees.
Google just called and gave me the job for getting in a slick plug for Google.

[wade]

answer to 2: Nothing! I'm a nickel!

[Anonymous]

#9: The utilitarian response: nothing would happen. The only way for an individual wife to prove her husband has cheated is to have the woman with whom he cheated to inform on him. The individual wife would probably not choose to put the question to all the women in the village on the risk that her husband might be implicated. The other women in the village would likely not inform, themselves being guilty of adultery and subject to sanction.

The Crucible response: assume a representative number of single, attractive women in the village are witches and interrogate them until a man (or men) are implicated in adultery.

[Matt]

1 hr = 60 min. 15 min = .25 hr.

@ 3:00 -> Min hand @ 12 Hrs, Hr hand @ 3 Hrs

@ 3:15 -> Min hand @ 3 Hrs, Hr hand @ 3.25 Hrs...

12 hrs = 360 degrees = 30 degrees per hr

.25 hrs = (30 deg/hr) X (.25 hr) = 7.5 degrees...

[John 2]

The answer to #2 is just to jump out. If I were reduced in size at my same density, then my legs would be strong enough to jump several times my own body length.

[bored csc employeee]

For #6 the answer is 24 not 11...

"In my day 3:15 mean't that the big hand was on 12, and the little hand on 3. That angle would be 90 degrees.
"
Since the days they invented the clock…big hand on 12 and little hand on 3 has always been 3:00...not sure what you are getting at...

[Googlite]

1. Depends on the size of the bus. But golf balls are quite efficient at filling the interior volume. Of course, you would need to make a small hole in the roof and shake the bus periodically to settle the balls. So really it's simply a question of measuring the interior volume. One way to do this of course would be to fill it with conveniently sized uniform objects, golf balls, for example ... Of course it is sickening to see time wasted on this kind of drivel when there's a nut in the Whitehouse.

[John Dodds]

Same questions that have been asked at Microsoft for years (how many pingpong balls needed to fill a jumbo jet) and featured in a number of books which people use to prepare for such interviews.

[Pradeep]

2. Sachhin, most blender blades are unscrewed at the bottom of the blender not in it. Plus there no way such a small proportioned person would be able to lift and break a glass blender. The way the blender blades are positioned would cause you to suctioned out if you laid down. The best bet would be to create a parachute type device with the clothes your wearing and thus get pushed out.

5. A database is like a mall. When you go in, you look at the board that shows you where each store is, you go to it, get your work done and get out.

17. With the clue i have no idea. Without the clue i would say give yourself 33 and two others the same. As two will agree with you, you live and still keep your money. The others ofcourse are out of money. evil huh :). i dont think ill get hired by google for this answer.

[JH]

Question one is best answered by a formula. Remember that USA and English golfballs have different volumes.

That's only 2 sentences to question #5, it specified that the answer be 3 sentences. :D

[Laurent]

Answer for #6 is not 11 nor 24.

They overlap every hour, except from midnight to 1am, and from 11pm to midnight.

That's 22.

[MC]

There are 24 hours ina day so clock hands would overlap 23 times.

[Richard Groff]

The volume of english and us golf balls is the same. The english ball used to be smaller, but that was done away with in the mid 1980s

[Matt]

2: Let myself be blended. The
systemic organ failure that would result from being shrunk to that size would be far more painful than a quick blend.
4: Use pointers--you can obtain their memory addresses.
6: 22, Laurent is right.
8: Sort by type (polo, tee, dress) and then by color (like the rainbow)
9: Nothing--since they know instantly when a husband is unfaithful, the queen is telling them nothing new.
10: 1 to 1. Every family has 1 boy, and the number of girls per family equals sum(0,inf,1/2^n) = 1
13: 1,2 cross (2); 1 crosses back (3); 5,10 cross (13); 2 crosses back (15); 1,2 cross (17)
14: This is a terrible bet--your expected return is 1*1/365-2*364/365 or about ($1.992) per person.
17: This is somewhat involved, you have to work backwards. If it's up to 2, 2 will split it 100-0 and have half the vote. If it's up to 3, he needs give 1 only one piece for him to have more than he would under 2's plan, so 99-0-1 passes. Similarly, 4's 99-0-1-0 passes, as 2 gets more than under 3's plan and thus votes for it. Doing this again means that 98-0-1-0-1 will pass.

[frogpuddle]

#6 Don't the hands overlap at the starting midnight? Then once each hour through the next midnight, accumulating a total of 25 overlaps?

Frogpuddle

[L. Wingo]

3. -> about $12.50 an hour

[David Burdon]

No.9

When the Queen turns up all the women in the village - except one - know already. The only exception is the offended wife. She immediately hunts down and kills her husband.

[Nick S]

Interpersonal relationships and people skills are important in an organisation. Who cares how many golf balls fit in a bus! Put that in your engine and google it.

[Dave]

1. 7 golf balls, I have 7 golf balls, however, I dont own a School bus.
2. Providing the density is not to intence, stand in the center.
3. $11 per hour + flight.
4. Look it up (Google search)
5. Something adults do to make themselves feel important/intelegent. You can look at what you've got, decide what you want and alter the facts. Pass.
6. What time does day start/finish? it's not a constant, lol! (14 aprox).
7. Just try anyway, the road is not a known entity, but not knowing makes the journey what it is.
8. Throw away the ones you no longer wear, arrange by colour. Put the shirt you couldn't find near the door.
9. The wives look for proof, unfortunately they can not determine which husband has been with which wife. DNA test kits are not available.
...tea break!

[Dave]

11. 0.95

[benoit perol]

it depends of the size of the school bus.

[Chris]

#13

Send across 1 and 2
Send back 1
Send across 10 and 5
Send back 2
Send across 1 and 2

Total: 17 minutes

[jack]

Ok, I am only going to shoot at a few I feel ok about. Don't have time to figure probabilities......

#1)80,800...golf balls...Per google, 404/cubic ft.....figure bus is 25'X8'.....

#2) DO nothing..you have fallen what probably amounts to 100 stories at that height and mass, you are dead.....

#3)nothing, when it rains it will wash all the windows for free.....

#6) 24

#7) google maps

#8) sort by color

#9) A man and a woman must be put to death.......99 woman will know the, including the one who cheated.....

12) 360 degrees....it is 3:15 not, 3:17 or 3:18...if they mean 7.5 degrees they need to frame the Q differently....

#16) leave one out and weight on the balance....if it is balanced, you left out the heavy one....if it tilts one way, you know of the 3 on that side, you have the heavy one....take one out of the 3, try to balance the 2, if they balance, you left the heavy one out, if it tilts, the down side is the heavy one.....

[Seattle Paul]

1. Depends what type of school bus.

2. If you are that small there is no reason to live anyway

3. I would hire another company to do and charge a 10% markup

4. A stack only grows up.

5. A database is like a cookie jar. You save cookies in it for retrival later. The cookie jar can only hold so many cookies.

6. 24

8. Use hangers

9. The queen obviously knows the man who has been unfaithful because she was unfaithful with him. Who ever is unfaithful with her should die.

10. Should be about 1.01 to 1 considering that the probablity of having a girl is slightly higher than that of a boy.

11. .95. Probablity is constant.

12. It will be 7.5 degrees

13. 1 and 2 should cross first 2Min
1 returns with light 1Min
10 and 5 cross 10Min
2 returns 2min
1 and 2 cross 2min
Total time 17 minutes

14. Depends if your friend gets the money from you or someone else. If it is someone else, take the bet because you are guaranteed $1, if not, don't take the bet.

16. Correct answer is above posted by P. Thomas

[Erik]

#1 A whole bus full

[nerd]

1. Used Google and it gave the Yahoo answer:
http://answers.yahoo.com/question/index?qid=20070906051002AAW3UrK
4. Sort your DVDs (books for the old fashioned who can read clocks) by title. Then make a list of actors (characters) and the films (books) they are in. Now choose all films (books) with a particular actor (character) ....
Such Queer Logic!

[Dan Man]

#9 All men are killed b/c the queen has cheated with all of them, making them all guilty

[EndGameOmega]

The answer to #9 is all the men die after 100 days.

[Paul]

Number of Golfballs that I can fit into a bus?

All of them.

When was the last time you saw a golf ball that was too large to fit into a school bus?

[Grun]

Why is everyone concerned about the density in the blender question? Your mass stays proportional and the density simply defines that proportion. The density of a cup of water is the same as the density of a gallon of water.

[Mike]

I'm pretty sure that the answer to question 11 is 63%.

P(no cars in 30 minutes)=0.05.
P (no cars in 10 minutes)=0.05^(1/3)=36.8%.
P(a car in 10 minutes)=1-36.8%=63.2%

[Lee Pefley]

How many golf balls can be fitted into a bus? Certainly one would fit, and maybe two as well!

[Z]

"#6 Don't the hands overlap at the starting midnight? Then once each hour through the next midnight, accumulating a total of 25 overlaps?

Frogpuddle"

you are almost right, it's 24, because the next midnight would be considered the next day

[Mycroft]

1. It says "you" so I could fit one then quit and move on to the next task.
3. I agree, $12.50 per hour plus materials.
14. Says "birthday" Mon through Sun so the odds are much better but how is up to you Math types.
16. Put 3 on each side, if they balance heavier one is in your hand. If they dont remove all balls and take two from the heavy side and place one on each side. you either have the heavy one in your hand or on the scale.
15. Not sure but I do know "you cant tune a piano but you can tuna fish"

[Harry]

Q16 is......
Place 3 balls on each side of the scale and retain 2.
If the scales balance you are holding the heavy one and a light one. Your compare only these 2 on your second weighing to find it.
If the scales drop on one side the heavy ball is one of these 3. For your second weighing place one ball on each side of the balance and retain one.
The balance will reveal the heavy ball if it is on the scale. If the they are equal you must be holding the heavy one.

[Ivan]

1. Oh I could definitely fit a couple in, I mean buses are huge and golf balls are only little aren't they? I can only hold about six golf balls at the same time though, so let's say six. Are we allowed more than one trip?

2. A number of things I suppose. I'd ask the person who put me in to take me out again, or use my remote control to either turn me back to normal size or to shrink the blender so that I could step out of it. That's if I was the one in control of the situation. If I was helpless in the grip of a mad evil scientist, I'd shout some heartfelt abuse at him and then spend my last 55 seconds thinking of my family before positioning myself so the end came quickly.

3. Ooooh a lot. $1,000 billion trillion, that's how much I'd charge cos I hate washing windows and the weather is terrible up there this time of year. Then I'd subcontract it out for a pittance, give half to charity which should cure all sorts and then take the rest of the money and buy myself a personal luxury island in the Caymans and sip chilled strawberry daquiris on the beach.

4. Ask the machineI suppose. Up? Does it matter which way up the machine is? these things are all relative aren't they.

5. Too easy! Besides he could probably already explain it to me in two.

6. 22. This is an Earth day we're talking about right? These questions are so bonkers you never know.

7. Make a plan to overcome any obstacles. Call for help - Ghostbusters! Power of Grayskull! Form Voltron! Transform! Take 'em down Master Chief! Start journey. Execute plan. Go first class all the way.

8. Get wife to make tea. Sit and drink tea while she looks for shirt for me, since she chooses what I wear anyway.

9. Not as if it's a surprise since the women already know every time a man is unfaithful. All the men will deny everything and all the women will act surprised and whisper a lot. I suppose it will all just pass over unless some schmuck panics and confesses in which case I guess his wife will kill him, Doh!

10. About 50:50. Cannot be exact because in some places where culturally they have exactly this policy (but not the addition of proactive female foeticide), you just get loads of girls being born and actually have more women than men. But that's the real world. If this is one of those hypothetical questions where you are supposed to work out probabilities etc. why don't they just ask a question about coloured smarties or something?

11. I guess the clue here is the phrase in brackets 'assuming constant default probability'. If I was clever I'd say 0.95 but because I'm a moron I'm going to ask is it the first or last ten minutes of the thirty minutes?

12. and 13. What he said. Gosh there's some clever people here. Apart from that tool that put the hands to 12.15 hahahaha

14. If it's one of those joint birthday parties then I'd take it. Otherwise no!

15. Are you serious? No idea, not one clue, wouldn't even know where to start. It would take years to find out because not everyone has an advert online and you'd have to assemble an army of auditors to check in phone books and classified ads in every city in the world, and by the time you got a number it would be incorrect because there are probably a few thousand who just qualified or just retired while you were reading this answer. What a stupid question - oh hang on, I have to remember there is no such thing as a stupid question, just stupid people. What's your next question?

16. If I had eight balls the same size I'd go see a doctor, pronto.

17. Based on prior pirate experience, 20 gold coins each. If you give any man less than an equal share he'll go off and join another gang. If your gang always gets equal shares then they will always be motivated for future jobs. And that's how you maximise your loot!

[Rick]

#16

Although a couple of people have had a pop at the answer, in each case they have mis read the question! There are eight balls, not 7 so you need to leave 2 out (not one), any two will do. If the scales balance, weigh those two you left out to discover which is the lighter one. If they dont, take the three balls that rise (one of them is light you see?) and weight any two. Again, if they balance, the un weighed one is the lightest, otherwise the scale will show who is your culprit.
I was surprised to see the people who had worked this out hadn't been able to read the question in the first place. No job at Google for them!

[David]

Rick - when the question asked for the one which weighs slightly MORE, why are you wasting your time looking for one which weighs slightly LESS

No job at Google for you son!

[David]

Question 9

Within about 5 minutes, every man is dead. Once the queen identifies the man who she cheated with (call him Husband A), Wife A screams, "you cheated on me - well I cheated on you with Husband B", whereupon wife B screams "you cheated on me - well I cheated on you with Husband C" etc etc etc

Question 10

The proportion of boys to girls is 1:1 (assuming the likelihood of a couple having either a boy or girl is equal). This is because after 500 couples have a boy and 500 couples have a girl, the 500 couples who had a girl then have another 500 kids, 250 of which are boys and 250 of which are girls. We now have 750 boys and 750 girls. The 250 couples etc etc etc.

[Andy]

Time for a scientific solution to the blender solution:
If you halve your height, the mass is divided by 8 (assuming the density stays the same, that's why it matters people), but the cross-sectional area of your muscles only by 4. So every time you halve your height you double your strength-to-weight ratio, which is why fleas can jump a long way with skinny legs, but elephants can't jump at all. So if you're shrunk to the size of a flea, make like a flea and jump out.
The only thing that worries me about this logic is that I've never had any reason to blend empty glasses, so I don't know exactly what a blender for them looks like or how it works.

[MRS SMITH]

I agree with "Bored CSC Employee" (Sept 22) that Q1 regarding extended drivel on golf balls is a waste of time, especially when we have a nut in the White House. Perhaps a more pressing question to ask is: How many nuts can you fit in the White House? I personally find considering this notion more sickening than wasting time answering the golf ball question.

[Andy]

Mrs Smith, you're missing the point - the reason there are such things as computers, the internet, blogs, discussion forums is that there are people whose brains have been trained by thinking such things; they may be nonsense in themselves but it's the thinking that matters. Of course I can't see any connection between brains and the white house...

[Bethany B]

My answer would be I am not sure, I would Goggle it.