Four of Us In Your Field

Four of us are in your field
But our differences keep us at yield

First, a one that is no fool
Though he resembles a gardener’s tool

Next, one difficult to split in two
And a girl once had one as big as her shoe

Then, to the mind, one’s a lovely bonder
And truancy makes it grow fonder

Last, a stem connecting dots of three
Knowing all this, what are we?

The four suits in a deck of standard playing cards

The Spade is a gardener’s tool.

The Diamond is the hardest gem to break. “Little Girl and Queen” is a Mother Goose rhyme, in which the Queen gave the girl a large diamond for picking the Queen some roses.

The Heart bonds with the mind to form love. Absence makes the heart grow fonder.

The Club, or Clover, is three dots connected around a stem.

Posted in Riddles

I Make Men Crazy

I can make men crazy,
I shine when you retire.
I move water without a touch,
My colors may cause you ire.

The moon. The moon has a long association with being crazy (lunar being the basis for a lunatic). It shines at night, when you go to bed. The moon’s gravity creates the ocean tides and when the moon is different colors it can mean bad weather is on its way.

Posted in Riddles

Only Self-Enumerating Number

What is the only self-enumerating number in English?

Four. The number four has four letters, making it self-enumerating. Interestingly, there are no self-enumerating numbers in French.

Posted in Brain Teasers

Speaks Without Words

What is it that speaks without any words?
And can be loudly and distinctly heard?
Will drive away friend, and foe alike.
And is enough to make a stolid man’s face alight?

Flatulence.

Posted in Riddles

How Many Fs?

Read this sentence.

   Finished files are the re-
   sult of years of scientif-
   ic study combined with
   the experience of years.

How many times does the letter F appear?

Six times. Most people skip the word ‘of’ and only count three.

Posted in Brain Teasers

The Ages of a Prince and Princess

A princess is as old as the prince will be when the princess is twice the age that the prince was when the princess’s age was half the sum of their present ages.

What are their ages?

This one took a while to figure out and there are numerous valid ways of finding the answer.

Here is the solution I came up with

I created the following table from the riddle:

 CurrentFuturePast
Princessx2z(x+y)/2
Princeyxz

I then created three equations, since the difference in their age will always be the same.
d = the difference in ages
x – y = d
2z – x = d
x/2 + y/2 – z = d

I then created a matrix and solved it using row reduction.

xyz
1-10d
-102d
.5.5-1d

It reduced to:

xyz
1004d
0103d
0015d/2

This means that you can pick any difference you want (an even one presumably because you want integer ages).
Princess age: 4d
Prince age: 3d

Ages that work

PrincessPrince
43
86
1612
2418
3224
4030
4836
5642
6448
7254
8060

To see other solutions check out the comments from when I posted this on my blog.

Posted in Brain Teasers

What is the Chance That You’ll Be Correct?

If you choose an answer to this question at random, what is the chance that you will be correct?

a) 25%
b) 50%
c) 60%
d) 25%

This is becomes a self-referential paradox. Both A and D would be correct if there were four unique answers, but since A and D are the same answer, the chance that you would choose a correct answer is 50%, which makes B correct. But if there’s only one correct answer, the odds of choosing the correct one at random goes back to 25%. And around and round you go.

There’s a lot of discussion at Richard Wiseman’s blog and more at Lifehacker, where I first saw this.

Posted in Brain Teasers

Add More But Weigh Less

The 17 items in your shopping cart weigh 8 pounds. But when your daughter puts in a ball, poster board and yo-yo the shopping cart weighs less. How is that possible?

Your daughter had to get out of the cart to fit the remaining items.

Posted in Brain Teasers

Longest Word Without Repeating Letters

What is the longest word without any repeated letters?

Uncopyrightable, with 15 letters and not a single one repeated. Dermatoglyphics, the study of fingerprints, works too.

Posted in Brain Teasers

Here Comes My Wife and Daughter

Two men are standing on one side of a bridge and two women are approaching them. One of the men says, “Here comes my wife and daughter” to which the second man replies, “Here comes my wife and daughter”. If they have not married the same woman and the women aren’t pregnant, how is this true?

The men are widowers and married each others’ daughter.

Posted in Brain Teasers