A U2 Concert

U2 has a concert that starts in 17 minutes and they must all cross a bridge to get there. All four men begin on the same side of the bridge. You must help them across to the other side. It is night. There is one flashlight. A maximum of two people can cross at one time. Any party who crosses, either 1 or 2 people, must have the flashlight with them.

The flashlight must be walked back and forth. It cannot be thrown and other tricks like that are not needed to solve the problem. The solution is simply a matter of allocating resources in a certain order. Each band member walks at a different speed. A pair must walk together at the rate of the slower man’s pace:

Bono: 1 minute to cross
Edge: 2 minutes to cross
Adam: 5 minutes to cross
Larry: 10 minutes to cross

For example: if Bono and Larry walk across first, 10 minutes have elapsed when they get to the other side of the bridge. If Larry then returns with the flashlight, a total of 20 minutes have passed and you have failed the mission.

This is one of my favorite brain teasers and I want to give you the satisfaction of figuring it out on your own. If you’re having a hard time, here’s a hint: There is a valid answer that doesn’t require tricks like throwing the flashlight or shining it backwards or having some other means of moving the flashlight.

There’s an assumption people often make that keeps them from solving this. Two members cross the bridge each time, but neither one of the two who crossed necessarily need to return. Think about how that would be possible. If you’re still stuck, use objects to simulate their movements. Use whatever you have laying around – pens, paper, erasers – and move them back and forth. Good luck!

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What is HIJKLMNO?

HIJKLMNO

What 5-letter word does this represent?

Water. Or literally, H to O, which sounds the same as H2O.

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Twice Is 99 More Than Half

What number satisfies this requirement? Twice the number is 99 more than half of the number.

66.

2 × 66 = 132 and 132 – 66 / 2 = 99.

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The Densest of My Clan

You ride on me every day but barely notice,
I’m hot and cold at the very same time,
I’m the densest of my clan,
And my first three help you enjoy music.

What am I?

Earth. Most people don’t stop to think that they’re hurtling through space on a huge planet. At any given time the Earth has burning hot magma and freezing arctics at the same time. The Earth is the densest planet and the first three letters, “ear” help you listen to music.

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Answer This Honestly

What question can you never honestly answer yes to?

Are you asleep? (or dead, or conscious, or being silent).

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Subtracting Ten From A Hundred

How many times can you subtract 10 from 100?

Only once. The next time you’d be subtracting 10 from 90.

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A Four Word Admonition

What four word admonition makes the happy person sad and the sad person happy?

The phrase, “This too shall pass.” According to Wikipedia, the well-known phrase is often attached to a fable of a great king who is humbled by these words, and to someone who is experiencing something wonderful, it can be saddening. But to one who is in the pits of despair, it is a phrase that brings relief and hope.

In other words, if a happy person is told, “This too shall pass” it will make them sad. But to a person on hard times, hearing, “This too shall pass” will cheer them up.

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Two Halves And a Whole

Complete the three missing words in the sentence, with the first two words combining to form the third word.

For example:

The prime minister ____ the meeting, even though the ____ was technically the ____ official.
The three missing words would be RAN, KING, and RANKING.

Now solve this one:

When she broke her ____ showing off at the ____ of the ski run, Arya became a ____ among her friends.

LEG, END, LEGEND

When she broke her LEG showing off at the END of the ski run, Arya became a LEGEND among her friends.

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What Can You Catch But Not Throw?

What can you catch but not throw?

Your breath or an illness (a cold, virus, the flu etc).

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Plum Taking

A man without eyes saw plums on a tree.
He neither took them nor left them, how can this be?

The man had only one eye and took one plum. (note singular versus plural)

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