Wednesday, February 16, 2011

Clock Synchronization

There is a clock at the bottom of the hill and a clock at the top of the hill. The clock at the bottom of the hill works fine but the clock at the top doesn't. How will you synchronize the two clocks.?

Obviously, you can,t carry either of the clocks up or down the hill! And you have a horse to help you transport yourself. And, the time required for going up the hill is not equal to the time required to go down the hill.

3 comments:

Shashank Mani said...

You have to go up the hill and come back, with horse, without horse, getting four equations to solve four unknowns - time to go uphill - with horse, without horse, time to go downhill - with horse, without horse. Then you can go up the hill and set the clock to ,(time when you left) + (time to go uphill with horse)

Anonymous said...

I believe this puzzle cant be solved!!!! How can there be four equations in this scenario???

Lets assume it takes 1 hour total for a round trip with horse & 3 hours for a round trip omn foot. This gives us only 2 equations:
Variables:
TUH = Uphill time with horse
TDH = Downhill time with horse
TU = Uphill time without horse
TD = Downhill time without horse

Equations:
TUH + TDH = 1
TU + TD =3

Plz let me know if I'm missing something.

Amit Bhatt
amitprbhatt@gmail.com

Anonymous said...

here we can assume that down clock has time T and the diff between upper clock and down clock is t.
Now
TUH = Uphill time with horse
TDH = Downhill time with horse
TUF = Uphill time without horse
TDF = Downhill time without horse
firstly we will go to with horse then we know about t+TUH
then we will come down we know about TUH+TDH
without horse up t+TUF
withour horse down TUF+TDF
there are 4 equation 5 unknowns but we can make 2 more equations
we go up with horse and come wihout horse then we know about TUH+TDF
similary TUF+TDH

6 equations 5 unkown...