Answers under spoiler:

1. In a small cabin in the woods, two men lay dead. The cabin itself is not burned, but the forest all around is burned to cinders. How did the men die?

2. You have a fox, a chicken and a sack of grain. You must cross a river with only one of them at a time. If you leave the fox with the chicken he will eat it; if you leave the chicken with the grain he will eat it. How can you get all three across safely?

3. You have 12 black socks and 12 white socks mixed up in a drawer. You're up very early and it's too dark to tell them apart. What's the smallest number of socks you need to take out (blindly) to be sure of having a matching pair?

4. What is special about the following sequence of numbers?

8 5 4 9 1 7 6 10 3 2 0

5. Three travelers register at a hotel and are told that their rooms will cost $10 each so they pay $30. Later the clerk realizes that he made a mistake and should have only charged them $25. He gives a bellboy $5 to return to them but the bellboy is dishonest and gives them each only $1, keeping $2 for himself. So the men actually spent $27 and the bellboy kept $2. What happened to the other dollar of the original $30?

6. You are the bus driver. At your first stop, you pick up 29 people. On your second stop, 18 of those 29 people get off, and at the same time 10 new passengers arrive. At your next stop, 3 of those 10 passengers get off, and 13 new passengers come on. On your fourth stop 4 of the remaining 10 passengers get off, 6 of those new 13 passengers get off as well, then 17 new passengers get on. What is the color of the bus driver's eyes?

7. A rooster lays an egg at the very top of a slanted roof. Which side is the egg going to roll off on?

8. 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.

9. Why is it very common to have a 9 minute snooze interval on alarm clocks, why not 10 instead?

10. An 18-wheeler is crossing a 4 kilometer bridge that can only support 10,000 kilograms and that's exactly how much the rig weighs. Halfway across the bridge a 30 gram sparrow lands on the cab, but the bridge doesn't collapse. Why not?

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1. It's the cabin of a plane and the plane crashed.

2. Take the chicken over first. Go back and bring the grain next, but instead of leaving the chicken with the grain, come back with the chicken. Leave the chicken on the first side and take the fox with you. Leave it on the other side with the grain. Finally, go back over and get the chicken and bring it over.

3. 3 socks. If the first sock is black, the second one could be black, in which case you have a matching pair. If the second sock is white, the third sock will be either black and match the first sock, or white and match the second sock.

4. The numbers are in alphabetical order.

(eight, five, four, nine, one, seven, six, ten, three, two, zero)

5. There is no missing dollar from the original $30 because after getting $1 back, the three travelers had paid a total of $27 for their room ($9 each), not $30. Out of that $27, the hotel has $25 and the clerk kept the remaining $2. If you still want to work from the original $30, the travelers have $3, the hotel has $25 and the bellboy has $2. The misleading part is adding the bellboy's $2 to the $27, when in fact it should be subtracted.

6. The eye color of the reader of this problem. The first sentence is the key: "You are the bus driver"

7. Neither, roosters don't lay eggs.

8. You get to figure this one 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 you from solving this. Two members cross the bridge each time, but neither one of the two the crossed need to return. Think about how that would be possible. If you're still stuck, use objects to simulate their movement. Use whatever you have laying around - pens, paper, erasers - and move them back and forth. Good luck!

9. By setting the snooze time to 9 minutes, the alarm clock only needs to watch the last digit of the time. So, if you hit snooze at 6.45, the alarm goes off again when the last digit equals 4. They couldn't make it 10 minutes, otherwise the alarm would go off right away, or it would take more circuitry.

10. Since the bridge is 4 kilometers long, the halfway point would be 2 kilometers. The 18-wheeler would have used much more than 30g of fuel to drive 2 kilometers.

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