Combine One-Third and Four-Fifths

How would you combine one-third of 12 and four-fifths of 7 to get 11?

Add EL (one-third of TWELVE) to EVEN (four-fifths of SEVEN) and get ELEVEN.

Posted in Brain Teasers

The Honest and Dishonest Guards

You’re in a room with two doors. There’s a guard at each door. One door is the exit, but behind the other door is something that will kill you. You’re told that one guard always tells the truth and the other guard always lies. You don’t know which guard is which. You are allowed to ask one question to either of the guards to determine which door is the exit.

What question should you ask?

Ask either guard what door the other guard would say is the exit, then choose the opposite door.

If you ask the guard who always tells the truth, he knows the other guard would lie, so he’ll point you to the door leading to death. If you ask the guard who always lies, he knows the other guard would truthfully show you the exit, so he’ll lie and point you to the door leading to death.

An alternate solution is to ask a guard what they would answer if you were to ask them which door was the exit, then choose that door. The truthful guard will point to the correct exit, but the lying guard will too. Here’s why. If you asked him what door was the exit, he would normally lie and point to the death door, but you asked him what he would say if you asked what door was the exit, and in order to lie to that question, he will point you to the exit.

Posted in Brain Teasers

Apples, Ice and Flowers

Apples, ice, and flowers can do it.
Pears, stones, and coins can’t.

Float.

By Sef Daystrom

Posted in Riddles

Two Four Three Five Six

0 2 4 3 5 6 8 9 7 11 10 12 13 14 15 16 18 17 20 21 22 19 24 23 26 25 28 29 27

What is the next number in the sequence?

31. The tenth number is 10 + 1 = 11. The twentieth number is 20 + 1 = 21, therefore the thirtieth number is 30 + 1 = 31.

Posted in Brain Teasers
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PINE Rebus

 P
INE

Pine cone (pine in the shape of a cone).

Posted in Riddles
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In Times Of War He Burns Asunder

Man walks over, man walks under,
In times of war he burns asunder.

What is it?

A bridge.

Posted in Riddles

Everybody Does At The Same Time

What is it that everybody does at the same time?

Grow older.

Posted in Riddles

Wily Winifred and the Case of the Odd Numbers

Mrs. Shine was having a rough day and wanted a break. So she asked her class to calculate the sum of the first 50 odd numbers. In a few moments, Winifred was at her desk with the correct answer of 2,500. Stunned, Mrs. Shine figured she must have gotten lucky, and sent precocious Winifred back to her seat with the task of finding the sum of the first 75 odd numbers. Again, Winifred returned in seconds with the correct answer (5,625).

How did Winifred find the answer so quickly?

Winifred, being the precocious child she is, realized there was a pattern when computing smaller sums of odd numbers.

First 3: 1 + 3 + 5 = 9
First 4: 1 + 3 + 5 + 7 = 16
First 5: 1 + 3 + 5 + 7 + 9 = 25

Do you see the pattern like our dear friend Winnie?

For the first n odd numbers, the sum is equal to n2. Thus the first 50 is 502, or 2,500, and the first 75 is 752, or 5,625.

Posted in Brain Teasers

Little Cat’s Feet

It comes in on little cat’s feet,
Is neither sour, nor sweet.
Hovers in the air,
And then is not there.

Fog or mist

Posted in Riddles

Up a Drainpipe Down but Not Down a Drainpipe Up

What can go up a drainpipe down but not down a drainpipe up?

An umbrella.

Posted in Riddles
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