## January 5, 2009

### Critical Reasoning Puzzle

A blindfolded man is asked to sit in the front of a carrom board.
The holes of the board are shut with lids in random order,
i.e. any number of all the four holes can be shut or open.
Now the man is supposed to touch any two holes at a time and
can do the following.

* Open the closed hole.

* Close the open hole.

* Let the hole be as it is.

After he has done it, the carrom board is rotated and again brought
to some position. The man is again not aware of what are the holes
which are open or closed. How many minimum number of turns does
the blindfolded man require to either open all the holes or close
all the holes? Note that whenever all the holes are either open or
close, there will be an alarm so that the blindfolded man will know
that he has won!!!!!

Secret SquÃ¯rrel said...

Only one if he's lucky, but if the board is rotated randomly he could go on forever, although he can always guarantee to put three holes into the same state after the first rotation.

Anonymous said...

whats a carrom board?

Anonymous said...

gilli danda

Anonymous said...

None. If any number of holes could be open or closed the board could start out with all holes open or closed, therefore it wouldn't take any rotations.