A horse is worth as much as two bulls and one sheep.

A bull is worth as much as two cows.

Two cows are worth as much as five donkeys.

A donkey is worth as much as four sheep.

How many sheep is a horse worth?

## Friday, April 29, 2011

## Thursday, April 28, 2011

### Net Figures

The numbers 1 up to and including 8 must be put in the circles of the depicted net. However, numbers in neighbouring circles must differ more than 1. So, for example, circles connected to a circle with a 4 may not contain a 3 or a 5.

Think that one was easy? Try this one.

The numbers 1 up to and including 9 must be put in the circles of the second figure in such a way that the sum of the corners of each of the 7 triangles (4 small ones and 3 large ones) is equal.

To answer in the comments, give the numbers in order for each row of the two figures.

Think that one was easy? Try this one.

The numbers 1 up to and including 9 must be put in the circles of the second figure in such a way that the sum of the corners of each of the 7 triangles (4 small ones and 3 large ones) is equal.

To answer in the comments, give the numbers in order for each row of the two figures.

## Wednesday, April 27, 2011

## Tuesday, April 26, 2011

### Anyone Else Back From Vacation?

Image via Wikipedia

In a contest, four fruits (an apple, a banana, an orange, and a pear) have been placed in four closed boxes (one fruit per box). People may guess which fruit is in which box. 123 people participate in the contest. When the boxes are opened, it turns out that 43 people have guessed none of the fruits correctly, 39 people have guessed one fruit correctly, and 31 people have guessed two fruits correctlyHow many people have guessed three fruits correctly, and how many people have guessed four fruits correctly?

## Monday, April 25, 2011

### In My Opinion, This is Hard to Do

This is a famous problem from 1882, to which a prize of $1000 was awarded for the best solution. The task is to arrange the seven numbers 4, 5, 6, 7, 8, 9, and 0, and eight dots in such a way that an addition approximates the number 82 as close as possible. Each of the numbers can be used only once. The dots can be used in two ways: as decimal point and as symbol for a recurring decimal. For example, the fraction 1/3 can be written as

.

. 3

The dot on top of the three denotes that this number is repeated infinitely. If a group of numbers needs to be repeated, two dots are used: one to denote the beginning of the recurring part and one to denote the end of it. For example, the fraction 1/7 can be written as

. .

. 1 4 2 8 5 7

Note that '0.5' is written as '.5'.

How close can you get to the number 82?

.

. 3

The dot on top of the three denotes that this number is repeated infinitely. If a group of numbers needs to be repeated, two dots are used: one to denote the beginning of the recurring part and one to denote the end of it. For example, the fraction 1/7 can be written as

. .

. 1 4 2 8 5 7

Note that '0.5' is written as '.5'.

How close can you get to the number 82?

## Thursday, April 14, 2011

### The Tax Man Cometh

(1) Everyone is afraid of the tax man.

(2) The tax man is afraid of only me.

Who am I?

(2) The tax man is afraid of only me.

Who am I?

## Wednesday, April 13, 2011

### Twice the Fun at Half the Price

Someone shows you two boxes and he tells you that one of these boxes contains two times as much as the other one, but he does not tell you which one this is. He lets you choose one of these boxes, and opens it. It turns out to be filled with $10. Now he gives you the opportunity to choose the other box instead of the current one (and give back the $10 from the first box), because the second box could contain twice as much (i.e. $20).

The Question: Should you choose the second box, or should you stick to your first choice to maximize the expected amount of money?

The Question: Should you choose the second box, or should you stick to your first choice to maximize the expected amount of money?

## Tuesday, April 12, 2011

### Letter Blocks

Molly has a set of four alphabet blocks. Each side of these blocks is printed with a different letter, making 24 in total. Molly notices that by rearranging the blocks, she can spell each of the following words:

BOXY, BUCK, CHAW, DIGS, EXAM, FLIT,

GIRL, JUMP, OGRE, OKAY, PAWN, ZEST

What letters are on each block?

BOXY, BUCK, CHAW, DIGS, EXAM, FLIT,

GIRL, JUMP, OGRE, OKAY, PAWN, ZEST

What letters are on each block?

## Monday, April 11, 2011

### Riddle of Bilbo

An eye in a blue face

Saw an eye in a green face.

"That eye is like to this eye"

Said the first eye,

"But in low place

Not in high place."

Saw an eye in a green face.

"That eye is like to this eye"

Said the first eye,

"But in low place

Not in high place."

## Wednesday, April 06, 2011

### So Here On Every Stop

Summer days make me want to play.

Hello, weather! What a beautiful day!

On the ground I see my bare feet.

Everyone knows it's time for a treat!

So, what is the answer to this riddle?

Hello, weather! What a beautiful day!

On the ground I see my bare feet.

Everyone knows it's time for a treat!

So, what is the answer to this riddle?

## Tuesday, April 05, 2011

## Friday, April 01, 2011

### Not Trying to Fool You, But Who Turned on the Snow?

I am used to bat with, yet I never get a hit.

I am near a ball, yet it is never thrown.

What am I?

I am near a ball, yet it is never thrown.

What am I?

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