Three Two Three Sequence

What number belongs at the beginning of this sequence?

?, 3, 2, 3, 9, 2, 4, 8, 4, 3, 7, 6

3 ½.

If you break up the numbers into groups of 4, a,b,c,d, then 2 × |a – d| = |b – c|.

9 2 4 8 → 2 × |9 – 8| = |2 – 4|, or 2 × 1 = 2
4 3 7 6 → 2 × |4 – 6| = |3 – 7|, or 2 × 2 = 4, so
n 3 2 3 → 2 × |3 ½ – 3| = |3 – 2|, or 2 × ½ = 1;

I’m not sure this is the correct solution, but it’s the best I’ve found so far. Email me if you know of a better one.

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Only Room You Can’t Enter or Leave

What’s the only room from which no one can enter or leave?

A mushroom.

A variation of this riddle is as follows.

I am a room with no doors and no windows, what am I?

Posted in Riddles

Hardware Store Costs

Ralph goes to the hardware store to buy something for his house. He asks the clerk how much one will cost and the clerk looks it up and tells him it will be $3. He asks about buying twelve and is told it will be $6. Two hundred will cost $9.

What is Ralph buying?

Door numbers at $3 each.

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Twenty from Three 3s

What’s the simplest way to make 20 using only three 3s (no other digits) and a combination of mathematical operations using any of these symbols?

+ – × / ^ ! √ . ()

(3 + 3) / .3 = 20

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Enjoyed By Some, Despised By Others

I am enjoyed by some, despised by others. Some take me for granted, some treasure me like a gift. I last forever, unless you break me first.

Marriage.

Posted in Riddles

I Met An Old Man On London Bridge

I met an old man on London bridge,
As the sun set on the ridge,
He tipped his hat and drew his name,
And cheated at the guessing game.

What was the man’s name?

Andrew. In the third line, “and drew his name”. It works better when you say it since the spelling is a bit off when written.

Posted in Riddles

A Big Pizza Pie

To get the most pizza, should you order two 12″ pizzas or one 18″ pie?

One 18″, with ~255 sumptuous square inches. Two 12″ pizzas would only give you ~226 square inches.

Note: The area of a circle is = πr2.

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Choose Your Own Death

A prisoner was brought before the King to be executed. The King was in a peppy mood and asked the prisoner how he would like to die. The prisoner told him and the King laughed heartily. The prisoner was released and sent on his way, alive.

What did the prisoner say?

He asked to die of old age.

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Lending Money to Darlene

Franklin lent Darlene as much money as she already had, then she spent $10. The next day, Franklin lent her as much money as she now had and again, she spent $10. On the third day Franklin once again lent her as much money as she now had and she spent $10, leaving her broke. How much money did Darlene start with?

$8.75
You may have been tempted to guess $30 because $10 is spent three times, but that would mean she would have had $60 ($30 lent plus the $30 she already had), and $50 after spending $10. The rest of the numbers end up at higher than zero, so we know it has to be less than $30. Even starting at $10 leaves Darlene with $10 on the third day. Starting with $8.75 works out as follows.

Day 1: $8.75 (lent) + $8.75 (already had) – $10 (spent) = $7.50 (remaining)
Day 2: $7.50 + $7.50 – $10 = $5
Day 3: $5 + $5 – $10 = $0

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Feet on the Hike

A man hiked through the woods with his dog and saw three coyotes, six wolf cubs, seven bunnies, nine squirrels and thirteen chipmunks. How many total feet were there?

Two. The man has two feet. The rest of the animals have paws.

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