Save this e-mail until you have some free time; then, plow away, and see how 
well you'd survive at Microsoft.

Take a shot at this one, and remember the clock is ticking.

Here's an analytical question Microsoft asks their interviewees.  Remember, 
you have to solve it quickly, you're in an interview.

The clock is now ticking.

You have 17 minutes to get all of them across to the other side.  It is 
night.  There is one flashlight.  A maximum of two people can cross at one 
time.  Any party who crosses, either 1 or 2 people, must have the flashlight 
with them.  The flashlight must be walked back and forth, it cannot be 
thrown etc.  Each man walks at a different speed.  A pair must walk together 
at a rate of the slower man's pace.

Man 1: 1 minute to cross.
Man 2: 2 minutes to cross.
Man 3: 5 minutes to cross.
Man 4: 10 minutes to cross.

For example, if Man 1 and Man 4 walk across first, 10 minutes have elapsed 
when they get to the other side of the bridge.  If Man 4 returns with the 
flashlight, a total of 20 minutes have passed, and you have failed the 
mission.

See how quickly you can solve this!

P.S.  The flashlight cannot shine a long distance.  No one can be carried, 
etc.  (This is a straightforward problem.  There are no tricks.)

Scroll down for the answer:






1 and 2 go over; 1 comes back = 3 minutes.
3 and 4 go over; 2 comes back = + 12 minutes = 15 minutes.
1 and 2 go over = 2 minutes = 17 minutes.  :  )