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

I Can Create Peace

My first is in alphabet, my third is in Guinness, my sixth is in donut and my eighth is in elephant. My fifth doesn’t appear in walrus, my second isn’t in stealth, but my seventh is in tremendous and my fourth is in horse. I can create peace.

What am I?

Everyone. Several words match the letter requirements, but only everyone satisfies the last statement. The other words are:

absentee
aperture
housetop
evermore

Posted in Riddles

Black Coat Rebus

What does this represent?

 black
-------
 coat

Black overcoat.

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The Roast with the Most

How do you spell roast?
How do you spell most?
How do you spell coast?
How do you spell post?

What do you put into a toaster?

Bread. (It turns into toast when it’s done toasting).

Posted in Brain Teasers

Counting Your Presents

According the song “The Twelve Days of Christmas”, how many total gifts were received?

364. Here’s the explanation.

Posted in Brain Teasers

How to Save Gas

If you could chose to increase the average fuel economy of a car, which of these would save the most fuel?

1. 10mpg -> 12mpg
2. 12mpg -> 15mpg
3. 15mpg -> 20mpg
4. 20mpg -> 30mpg
5. 30mpg -> 60mpg

It turns out they all save the same amount of fuel.

If you travel 100 miles:

100 / 10 = 10 gallons used
100 / 12 = 8 1/3 gallons used

10 – 8 1/3 = 1 2/3 gallons saved

100 / 30 = 3 1/3 gallons used
100 / 60 = 1 2/3 gallons used

3 1/3 – 1 2/3 = 1 2/3 gallons saved

Posted in Brain Teasers

A Most Unusual Paragraph

This is an unusual paragraph. I’m curious as to just how quickly you can find out what is so unusual about it. It looks so ordinary and plain that you would think nothing was wrong with it. In fact, nothing is wrong with it! It is highly unusual though. Study it and think about it. You still may not find anything odd. But if you work at it a bit, you might find out. Try to do so without any coaching.

The letter “e” is the most common letter in the English language, yet it never appears in the entire paragraph.

Posted in Brain Teasers

I Never Even Touch the Ground

For some, I am used to get around.
I never even touch the ground.
Sometimes I fall and sometimes I float,
If I’m in the air, then take note.

What am I?

A boat. Boats are used to get around, they aren’t on the ground, but in the water. They rise and fall with the waves, and if they’re in the air, it may be due to rough seas and you should be careful.

Another possible answer is a blimp.

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Head, Tail, Brown and No Legs

What has a head, a tail, is brown, and has no legs?

A penny.

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Two Hands But Can’t Clap

I have two hands but I cannot clap. What am I?

A clock.

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