Riddles and Brain Teasers

Ten Times Two is 0218

10 × 2 = 0218
20 × 2 = 1421
30 × 2 = 1632
40 × 2 = ?

2840.This makes the first column the start of the Fibonacci series: 0, 1, 1, 2.
The second column is the even numbers: 2, 4, 6, 8
The third column is counting up by ones: 1, 2, 3, 4
And the last column is the answer in the first row in reverse: 8, 1, 2, 0.Don’t ask what 50 × 2 equals. I have no idea. :)Thanks to Jim for helping with the solution.

2840.

This makes the first column the start of the Fibonacci series: 0, 1, 1, 2.
The second column is the even numbers: 2, 4, 6, 8
The third column is counting up by ones: 1, 2, 3, 4
And the last column is the answer in the first row in reverse: 8, 1, 2, 0.

Don’t ask what 50 × 2 equals. I have no idea. :)

Thanks to Jim for helping with the solution.

Posted in Brain Teasers

Tagged with Series

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?

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$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

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

Posted in Brain Teasers

Two More Seconds

Ida puts her coffee into the microwave, as she does every morning, for exactly two minutes. When the microwave goes off, she opens the door, but then closes the door again and sets the microwave for two more seconds. What good would two more seconds be?

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To rotate the handle on the mug so she can comfortably remove it.

Posted in Brain Teasers

Rotating Coins Around Coins

You have two coins of equal size on a table, situated end to end vertically. If you roll the top coin around the bottom coin until it returns to its original position, how many times will it have rotated?

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Twice. See this video for more details.

Posted in Brain Teasers

A C F H K ?

What is the next letter in this sequence and why? A C F H K _

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M. Skip 1 letter then 2 letters, alternating.

Posted in Brain Teasers

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.

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Marriage.

Posted in Riddles

All The Numbers of The Phone

What do you get when you multiply all of the numbers on a phone’s number pad?

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Zero.

Posted in Brain Teasers

A Sunday Morning Murder

A man was killed on Sunday morning. His wife found the body and called the police. The police arrived and questioned the chef, maid, butler, and gardener. Their alibis were:

Chef – making breakfast
Maid – getting mail
Butler – setting table
Gardener – watering plants

The police immediately arrested the criminal. Who was it and how did they know?

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The maid. Mail isn’t delivered on Sunday.

Posted in Brain Teasers