A Perfect Gentleman

He was the perfect gentleman even though his nephew couldn’t see it. Who was he?

A fine chap with a blind nephew (or an exemplary uncle who died before his nephew was born).

Posted in Brain Teasers

The Bookworm

A bookworm eats from the first page of an encyclopedia to the last page in a straight line. The encyclopedia consists of ten 1000-page volumes and is sitting on a bookshelf in the usual order. Not counting covers, title pages, etc., how many pages does the bookworm eat through?

        __                             __
      B|  |                           |  |F
      A|1 |...........................|10|R
      C|  |                           |  |O
      K|  |                           |  |N
       |__|                           |__|T
      -------------------------------------

On a book shelf the first page of the first volume is on the “inside”, so the bookworm eats only through the cover of the first volume, then 8 times 1000 pages of Volumes 2 – 9, then through the cover to the 1st page of Vol 10 for a total of 8,000 pages.

Note: The question asks how many pages, not how many sheets of paper.

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BEJQXYZ

What is significant about the following set of letters?

BEJQXYZ

They are the only letters in the alphabet that are not found at the beginning of the name of a state in the United States of America. The rest of the letters in the alphabet, namely ACDFGHIKLMNOPRSTUVW, start the name of at least one state. Incidentally, eight different states each start with the letters M and N, tying them for the most states starting with a particular letter. The next highest is a three-way tie between A, I and W with four each.

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Cut One Off And I Become Stronger

I have three letters. Cut one off and I become stronger. Cut two off and I become ten. What am I?

A fox. Removing the f leaves ox, a strong animal. Cutting off the fo leaves X, the roman numeral for 10.

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False Positive HIV Test

Imagine an HIV test that is 95% accurate (false positive rate of 5%) and around 2% of the tested population is infected with HIV. What is the probability that you actually have HIV when your test comes back positive?

29%

To read more about this, see the False Positive Paradox page on Wikipedia.

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Look at My Face

If you look at my face you won’t see 13 in any place. What am I?

A clock face. It only has the numbers 1 through 12.

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I Am Here, I Am There

I am here, I am there
I am burned into the mind of none
I walk on fire and live on ice
My words are meaningless for I talk not
I hate everyone yet fear no one
I have lived for centuries
Yet I have never existed
What am I?

Nothingness.

Posted in Riddles

Six Letter Word

What 6-letter word has the same pair of letters in spots 1 and 5, a different pair in spots 2 and 6 and contains a ‘u’ in between?

church, delude, inulin or recure

Posted in Brain Teasers

Sometimes I’m a Sphere

Sometimes I’m a sphere,
Sometimes I’m a banana,
And sometimes I’m not there at all.

What am I?

The moon. A full moon is a sphere, a crescent moon looks like a banana, and sometimes the moon is not visible at all.

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What Is The Longest Word With Horizontal Symmetry

A word with horizontal symmetry is one whose letters are a mirror image of themselves. If you drew a horizontal line across the word and folded it over, it would overlap on itself. For example, EXCEEDED and ICEBOX have horizontal symmetry, but VERTICAL and SIMPLE do not.

What is the longest word with horizontal symmetry?

CHECKBOOK.

Posted in Brain Teasers