## December 28, 2010

### World War 1 riddle

A grandfather is telling his grandson war stories.

"At the end of World War 1, I was awarded for my bravery
after saving a group of my men," the grandfather says.

"You see, we were fighting in northern France and one of our
enemies threw a grenade at us. I managed to pick it up and
throw it away before it exploded. So right after the war
ended, a General gave me a sword, engraved with the words
'Awarded for Bravery and Valor, A True Hero, World War 1'".

"The grandson thinks about the story for a minute and then
says "Grandpa, that story can't be true!"

How did the grandson know?

## December 19, 2010

### An Unusual Paragraph

This is a most unusual paragraph. How quickly can you find
out what is so unusual about it? It looks so ordinary, you'd
think nothing was wrong with it. Actually, nothing is wrong
with it. But it is not as ordinary as you might think.
If you think about it for a bit, you will find out why it
is truly so unusual. So what is it? What is so unusual about
this paragraph?

## December 16, 2010

### Millionaire and Hats

A millionaire bought a job lot of hats 1/4 of which were brown.
He sold 2/3 of the hats including 4/5 of the brown hats.
What fraction of the unsold hats were brown.

## December 1, 2010

### Hourglass Puzzle

You have 2 hourglasses, a 7 minute hourglass and an 11 minute
hourglass, what is the quickest way to time the boiling of
an egg for 15 mins?

## November 17, 2010

### if a 0.1mm paper is folded 100 times...

if a 0.1mm paper is folded 100 times then what will be the thickness
of it after 100 foldings?

## November 3, 2010

### English sentence with all the letters

Would anyone know the shortest sentence in the English language
that has every letter of the alphabet?

## October 7, 2010

### Clock Angles

How many times are the hands of a clock at right angle
in a day?

## September 14, 2010

### Water jar puzzle

You have three jars that hold max 19, 13 and 7 liters of water
respectively. 13 and 7 litre jars are full of water and 19 litre jar
is empty (so total 20 litres of water).

You can pour water between jars and I want two jars with 10
litres of water (ie 10, 10, 0 from 0, 13, 7)

## August 30, 2010

### Unlock the Safe

There is a safe with a 5 digit number as the key. The 4th
digit is 4 greater than the second digit, while the 3rd digit
is 3 less than the 2nd digit. The 1st digit is thrice the
last digit. There are 3 pairs in the number whose sum is 11.

Find the number.

## August 17, 2010

### 3x3x3 wooden cube

Imagine a 3x3x3 wooden cube.

How many cuts do we need to break it into 27 1x1x1 cubes?

## July 11, 2010

### Crossing the river

Two boys want to cross a river. The only way to get to the other
side is by boat, but that boat can only take one boy at a time.
The boat cannot return on its own, there are no ropes or similar
tricks, yet both boys manage to cross the river using the boat.

How they manage to cross?

## June 8, 2010

### Five Pirates

5 pirates of different ages have a treasure of 100 gold coins.

On their ship, they decide to split the coins using this scheme:

The oldest pirate proposes how to share the coins, and all pirates
remaining will vote for or against it.

If 50% or more of the pirates vote for it, then the coins will be shared
that way. Otherwise, the pirate proposing the scheme will be thrown
overboard, and the process is repeated with the pirates that remain.

Assuming that all 5 pirates are intelligent, rational, greedy,
and do not wish to die, (and are rather good at math for pirates)
what will happen?

## May 28, 2010

### Anil & Mail

Anil has to receive a mail from Station, but the train arrives
early and the mail is then sent by a cart to him. Both Anil and
cart met in the middle in 30 mins. Due to this in whole journey
anil saved 20 mins, due to eary arrival of train.

Now tell me how early the train arrived?

## May 7, 2010

### Profit Maximization

A manufacturer can sell X items (X >= 0) at a price of Rs. (330 - X)
each. The cost of producing X items is ((X^2) + 10X + 12).
Determine the no. of items sold so that the manufacturer can make
the maximum profit..

## April 27, 2010

### Find the profit of the horse deal ?

A man decides to buy a nice horse. He pays \$60 for it, and he is
very content with the strong animal. After a year, the value of the
horse has increased to \$70 and he decides to sell the horse.
But already a few days later he regrets his decision to sell the
beautiful horse, and he buys it again. Unfortunately he has to pay
\$80 to get it back, so he loses \$10. After another year of owning
the horse, he finally decides to sell the horse for \$90.

What is the overall profit the man makes?

## April 20, 2010

### Solve 2 3 4 15 12 3 4 5 28 20 4 5 6 45 30 5 6 7 66 42 6 7 8 ? 56

Find the missing number ?

2 . 3 . 4 . 15 . 12
3 . 4 . 5 . 28 . 20
4 . 5 . 6 . 45 . 30
5 . 6 . 7 . 66 . 42
6 . 7 . 8 . ?? . 56

## April 17, 2010

### Chocolates

A shop sells 1 chocolate at Rs:1 each, You can exchange 3 wrappers for a chocolate. If you have Rs:15, then how many chocolates can you totally get ?

1) with Rs:15 you will get 15 chocolates --->15 wrappers
2)15 wrappers /3 = 5 chocolates ------> 5 wrapers
3) 5 wrappers /3 = 1 chocolate +2 wrappers------->3 wrappers
4) 3 wrappers / 3 = 1 chocolate

Total chocolates = 15+5+1+1 =22

Check also : How many Chocolates you will get if you have Rs. 45

## April 8, 2010

### 60, 30, 20, 15, ?, ?

Find next two numbers in the series:
60, 30, 20, 15, ?, ?

## March 26, 2010

### Find the least number

Find the least number which when divided by 35, leaves remainder 25;
when divided by 45, leaves remainder 35 and
when divided by 55, leaves remainder 45 ?

## March 17, 2010

### Bet

I bet you for Rs. 100 that if you give me Rs. 200, I will give you
Rs. 300 in return.

Would you bet with me? Why?

## March 9, 2010

### Secret agents

There are N secret agents each know a different piece of secret
information. They can telephone each other and exchange all the
information they know. After the telephone call, they both
know anything that either of them knew before the call. What are
the minimum number of telephone calls needed so that all of
them know everything?

## March 5, 2010

### 1 1 2 1 2 2 3 1 2 2 3 2 3 3 4 1 2 2 3 2 3 3 4 2 3 3 ?

What are the next three numbers in the given series?

1 1 2 1 2 2 3 1 2 2 3 2 3 3 4 1 2 2 3 2 3 3 4 2 3 3 _ _ _ ?

## March 2, 2010

### Phone number permutation

If you were to dial any 7 digits on a telephone in random order,
what is the probability that you will dial your own phone number?

Assume that your telephone number is of 7-digits.

## February 23, 2010

### Find the correct statement

A sheet of paper has statements numbered from 1 to 100. Statement
N says "Exactly N of the statements on this sheet are false."

How many statements are true?

## February 22, 2010

### Tough probability riddle

A stick of length 1 metre is divided randomly into 3 parts.
What is the probability that a triangle can be made with
those three parts?

### Rooks problem

Consider a chessboard with a single Rook. A Rook can move any
number of square sideways/forward, but not diagonally.
What is the minimum number of moves the Rook needs to make, in
order to pass over all the squares on the chessboard and return
to the original position?

Note: Take any square as a starting position for the Rook.

## February 15, 2010

### Hot Dogs

If a boy and a half can eat a hot dog and a half in a minute and a half,
how many hot dogs can six boys eat in six minutes?

## January 27, 2010

### Coffee machine

A drinks machine offers three selections - Tea, Coffee or Random
(Either tea or Coffee)but the machine has been wired up wrongly
so that each button does not give what it claims. If each drink
costs 50p, how much minimum money do you have to put into the
machine to find out which button gives which selection?