The Potato Paradox

Fred brings home 100 pounds of potatoes, which (being purely mathematical potatoes) consist of 99 percent water. He then leaves them outside overnight so that they consist of 98 percent water. What is their new weight?

50 pounds.

100 lb of potatoes with 99% water weight means there’s 99 lb of water and 1 lb of solids, a 1:99 ratio.

If the water decreases to 98%, then the solids account for 2% of the weight. The 2:98 ratio reduces to 1:49. Since the solids still weigh 1 lb, the water must weigh 49 lb for a total of 50 lbs for the answer.

Read more at the Potato Paradox wikipedia page.

Posted in Brain Teasers

I Am What Remains

I am what remains of what
was once a living whole,
dug in deep, protruding, though,
and unobtainable.

A stump.

By Sef Daystrom

Posted in Riddles
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Graphical Rebus Two

What does this rebus represent?

Rebus

Castle on a Cloud

Posted in Riddles
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Full of Holes Yet Full of Water

I’m full of holes, yet I’m full of water. What am I?

A sponge.

Posted in Riddles

I Am a Protector

I am a protector.
I sit on a bridge.
One person can see right through me.
Others wonder what I hide.

What am I?

Sunglasses

Posted in Riddles
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Keys to Unlock Your Soul

I am a box that holds keys without locks, yet they can unlock your soul. What am I?

A piano.

Posted in Riddles

What Letter Comes Next?

The letters in this series are ones that don’t begin something. Figure out what that something is, and what letter comes next.

B E J ?

Q. The thing they don’t begin is states in the United States of America. The final three letters in the series are X, Y and Z.

Posted in Brain Teasers

Rhonda At the Ballet

Rhonda will go see ballet but not the opera. Her favorite number is eight and she doesn’t like nine. She likes salmon but not trout. She hates Mondays and likes Wednesdays. Does she use a comb or a brush?

A comb. Rhonda likes words with silent letters, like her name.

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

JAJWUTH

JAJWUTH
TFAPOW
JFDABHC

What are the next five letters in this sequence?
Hint: Think back to childhood rhymes.

AJCTA. These are the first letters from the nursery rhyme, “Jack and Jill Went Up The Hill”. AJCTA represents, “and Jill came tumbling after”.

Posted in Brain Teasers