Riddles and Brain Teasers

Gain and Lose the Most

Some are quick to take it.
Others must be coaxed.
Those who choose to take it
gain and lose the most.

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Risk.

By Sef Daystrom

Posted in Riddles

What Times Seven Is All Fours?

What is the smallest integer that is all 4s when multiplied by 7?

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63,492 × 7 = 444,444

Posted in Brain Teasers

Two Three Four Fifteen

What is the missing number?

2 3 4 15 12
3 4 5 28 20
4 5 6 45 30
5 6 7 66 42
6 7 8 ?? 56

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91. To get the number in the fourth column, you add the numbers in column 1 and 2, then multiply by the number in column 2. f(n,m) = (n + m) * m
For example, f(2,3) = (2 + 3) * 3 = 15. Thus f(6,7) = (6 + 7) * 7 = 91

Posted in Brain Teasers

Tagged with sequence

The Pattern of Numbers

These series follow a pattern.
2 4 8
1 17 476
65 20987 3571890

This series does not follow the pattern
18 79 45

What is the pattern?

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The numbers must be in ascending order. This can be a fun one to have people work out in person, as they test out three-number series and you can tell them whether or not they satisfy the pattern.Thanks to Patrick for sending this in and thanks to this video from Veritasium for inspiring Patrick.

The numbers must be in ascending order. This can be a fun one to have people work out in person, as they test out three-number series and you can tell them whether or not they satisfy the pattern.

Thanks to Patrick for sending this in and thanks to this video from Veritasium for inspiring Patrick.

Posted in Brain Teasers

Important Rebus

What does this represent?

IMPORTANT = IMPORTANT

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Equally important.

Posted in Riddles

Tagged with rebus

What Surrounds The World

What surrounds the world, yet dwells within a thimble?

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Space.

Posted in Riddles

Kevlar, Fire Escapes and Wipers, Oh My!

What do computer compilers, kevlar, fire escapes and windshield wipers all have in common?

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They were all invented by women.A variation of this brain teaser includes laser printers (they were invented by Gary Starkweather) and bulletproof vests (invented by Casimir Zeglen using silk, though modern vests use Kevlar, so it’s halfway right).

They were all invented by women.

A variation of this brain teaser includes laser printers (they were invented by Gary Starkweather) and bulletproof vests (invented by Casimir Zeglen using silk, though modern vests use Kevlar, so it’s halfway right).

Posted in Brain Teasers