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SYMBOLS

MNeeds math past arithmetic and basic probability.
CRequires knowing how to play chess.
PPhysics knowledge is helpful.
>=PI don't know the solution to this problem myself.
CPURequires calculator/computer power.


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RECENT ADDITIONS

Check out latest puzzles by perusing the forum and the 10 most recent posts. Latest additions to cover site can be seen by clicking here.

micro$oft
HOW MANY ... How many cars are there in the USA? How many barbershops are there in the USA? How many diapers are there in the USA?
M&Ms How are M&Ms made? (I kid you not)
BATHROOM DESIGN

You have been assigned to design Bill Gates bathroom. Naturally, cost is not a consideration. You may not speak to Bill.

Forum thread: click here
SALT SHAKER Explain a scenario for testing a salt shaker.
KEY TURNING Which way should the key turn in a car door to unlock it?
STATE REMOVAL

If you could remove any of the 50 states, which state would it be and why?

Forum thread: click here
U SMART y do u think u r smart
HOTEL HOT WATER Why is it that when you turn on the hot water in any hotel, for example, the hot water comes pouring out almost instantaneously?
CLOCK DISASSEMBLY If you had a clock with lots of moving mechanical parts, you took it apart piece by piece without keeping track of the method of how it was disassembled, then you put it back together and discovered that 3 important parts were not included; how would you go about reassembling the clock?
KEYBOARD DESIGN How would you go about building a keyboard for 1-handed users?
COFFEE MACHINE DESIGN How would you design a coffee-machine for an automobile?
Y WORK HERE? y do u wanna work at Microsoft?
LIGHT DILEMMA Suppose you go home, enter your house/apartment, hit the light switch, and nothing happens - no light floods the room. What exactly, in order, are the steps you would take in determining what the problem was?
MIRROR OPTICS Imagine you are standing in front of a mirror, facing it. Raise your left hand. Raise your right hand. Look at your reflection. When you raise your left hand your reflection raises what appears to be his right hand. But when you tilt your head up, your reflection does too, and does not appear to tilt his/her head down. Why is it that the mirror appears to reverse left and right, but not up and down?
QUARTER STACKING ESTIMATE Suppose that I have a closet with a base area of 4ft by 8 ft, and a height of 10ft, and that the closet is completely filled with quarters. Now I take out that closetful of quarters and stack them atop each other, one by one. Will the resulting stack be higher, lower, or about the same height as the Empire State Building?
LIGHT PHYSICS

A person on the earth sees a satellite some distance D away giving off a ray of light. How much energy must the light contain? You are allowed to ask questions for more information.

Note: This is actually a problem from Agilent Labs. The guy who got this problem was not applying for a position related to light physics at all ... in fact, he had not even taken Physics 7C (optics and quantum mechanics at UC Berkeley). Plus he came late. So he didn't get the job.
HOSPITAL ELEVATOR TESTING How would you test a new elevator that will be placed into a hospital, but you don't have access to the hospital?
UC BERKELEY IN SF BIZ DISTRICT

If you were to move the UC Berkeley campus into the San Francisco business district, what would you do?

Note: Yes, this is an actual question they asked, apparently for a program manager position.
MOVING BUS DIRECTION 
    _______________________________________
   /                                       \
   |   0   0   0   0   0   0   0   0   0   |
   |                                       |
   |                                       |
   |___/---\_______________________/---\___|
         0                           0

This is a picture of a bus (drawn symmetrically). The bus is moving forward. Which way is the bus moving, to the right or to the left? You may ask as many questions as you need to determine the answer.

Note: Although this can be answered cold, the questioner usually wants to see the process you use to determine the answer.
TOOTH FAIRY COMPANY

Your company is bidding for the tooth fairy management contract. Ignoring administration, transportation, wages, etc., how much will it cost to pay out the money every year at $0.25 per tooth?"
MS BULB JOKE

How many Microsoft engineers does it take to screw in a light bulb?

Note: ok, so this didn't come from a microsoft interview :)
REMOTE CONTROL DESIGN

I am a venture capitalist providing you with money for a remote-control start up firm. Design a remote control that will make me rich.

Note: From an Mickey$oft internship interview!
TEMPERATURE OUTSIDE

2/3/2003 3:57PM

You are in a building, and you want to know what the temperature is outside. How do you do it?

Note 1: The way this riddle works is, after you mention a possible solution, the interviewer says that solution is not possible and asks what else you can do. So the scenario gets increasingly difficult, and it comes down to coming up with as many solutions as you can.

Example Dialogue:

You: "Well you could use X to find the temperature"
Them: "OK let's say there are no X's lying around"
You: "OK, perhaps you could try Y"
Them: "Y is broken, what else"

Note 2: I was actually asked this question by Microsoft! The interviewer was Andrew Gottelieb.

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