Twice the Sum of Its Digits

What number is twice the sum of it’s digits?

18.

1 + 8 = 9
2 × 9 = 18

Posted in Brain Teasers

Next in the Sequence

Here is a series of numbers. What is the next number in the sequence?

1
11
21
1211
111221
312211

13112221

The next number in the series counts the previous numbers. Thus the first number is 1, which is one 1, or 11. To describe 11, you have two 1’s, or 21. Now you have one 2 and one 1, so the next number is 1211. The solution is to continue describing the previous number using only numbers.

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Find the Three Mammals

The largest crowd at the flea market came looking for bargains.
I took off the peel and ate the banana.
He has no judgement, no sense altogether.

Find the three mammals in these statements.

1. Camel (CAME Looking)
2. Eland (peEL AND)
3. Seal (senSE ALtogether)

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Bank Wait Times

Suppose a small bank has one teller and customer transactions take 10 minutes on average. With 5.8 customers arriving per hour, what is the expected wait time? What would it be if you added a second teller?

With one teller, customers will wait nearly five hours on average. But adding a second teller makes the wait go down to 3 minutes.

Thanks to John D. Cook for this one.

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Liquid In Nature

I am liquid in nature,
But don’t bend me to far,
For then I may break
And give you a scar.

What am I?

Glass. Technically, glass is an amorphous solid, but that doesn’t have the same ring to it.

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Alter By a Single Stroke

How can you alter the following equation by a single stroke to make it correct?

5 + 5 + 5 = 550

5 4 5 + 5 = 550

Add a diagonal line on the top left of the first plus sign to convert + into a 4. You could also put a slash through the equal sign to make ≠ (not equal) but that’s not as cool.

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A Woman Shoots Her Husband

A woman shoots her husband, then holds him under water for five minutes. Finally, she hangs him. Five minutes later they enjoy a wonderful dinner together. How can this be?

She took a photo of him and developed it in the dark room.

Posted in Riddles

Hear a Lot, Say a Lot

I hear a lot
And I say a lot
Few ever look for me
And even fewer ever hear me
I hide in plain sight
Whether its day or night
To help is all I want
But most like to bend me
And as if they had a wand
Never again shall anyone find me
They do this to control
Without realizing the high price of a soul
But when I’m least expected
They’d rather be protected
For there shall be no place to hide
What am I?

The truth.

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How to Stay Dry?

A group of ten people are going out for pizza but only two of them have an umbrella to keep them dry. Somehow they are able to walk all the way to the pizza place without getting wet. How?

It’s not raining.

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Graphical Rebus Five

What does this rebus represent?

Rebus

I Feel the Earth Move

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