Handshake Problem

Jack and his wife went to a party where four other married
couples were present. Every person shook hands with everyone
he or she was not acquainted with. When the handshaking was
over, Jack asked everyone, including his own wife, how many
hands they shook. To his surprise, Jack got nine different
answers. How many hands did Jack's wife shake ?

Lawn Puzzle

Grass in lawn grows equally thick and in a uniform rate.
It takes 24 days for 70 cows and 60 days for 30 cows to eat
the whole of the grass. How many cows are needed to eat
the grass in 96 days?

Substitute digits for the letters

Substitute digits for the letters to make the following relation true.
W O R L D
+ T R A D E
-------------
C E N T E R

[Note that the leftmost letter can't be zero in any word. Also, there
must be a one-to-one mapping between digits and letters.
e.g. if you substitute 3 for the letter W, no other letter can be 3
and all other W in the puzzle must be 3. ]

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!!!!!

Find the next in the series

AZFR, LARU, AMAS, SBNS, KICI, ????

8 Ball Problem

You have eight almost identical balls, but one of them is
a little bit lighter than the others. It is not that lighter,
though, that you can tell the difference by hand, but you
have a two-armed balance. How can you find the light
ball with only two measures?

Fun Logic Puzzles

Syam was looking at a photo. Someone asked him, "Whose picture
are you looking at?" He replied: "I don't have any brother or
sister, but this man's father is my father's son."
So, whose picture was Syam looking at?