## Can't open any doors

What has many keys but can't open any doors?

Piano.

What has many keys but can't open any doors?

Piano.

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You are in a cabin and it is pitch black. You have one match on you. Which do you light first, the newspaper, the lamp, the candle, or the fire?

You light the match first!

The Smith family is a very wealthy family that lives in a big, circular home. One morning, Mr. Smith woke up and found his gardener's body. He knew it was one of his employees who had killed him. So he asked them what they were doing in the morning and he got these replies.
Driver: "I was outside washing the car."
Maid: "I was dusting the corners of the house."
Cook: "I was starting to make lunch for later."
From the replies he knew who the killer was. Can you guess who it was?

The maid, because they lived in a circular house and she was apparently "dusting the corners" of the house at the time of the murder - the house is round, therefore it has no corners.

Your friend pulls out a perfectly circular table and a sack of quarters, and proposes a game.
"We'll take turns putting a quarter on the table," he says. "Each quarter must lay flat on the table, and cannot sit on top of any other quarters. The last person to successfully put a quarter on the table wins."
He gives you the choice to go first or second. What should you do, and what should your strategy be to win?

You should go first, and put a quarter at the exact center of the table.
Then, each time your opponent places a quarter down, you should place your next quarter in the symmetric position on the opposite side of the table.
This will ensure that you always have a place to set down our quarter, and eventually your oppponent will run out of space.

A blind man walks into a hardware store to buy a hammer. There are hammers hanging behind the front desk, but obviously the blind man isn't able to see them. And yet a few minutes later, he happily walks out of the store, having just purchased a new hammer.
How did he do it?

He walks up the the front desk where the clerk is working and says "I'd like to buy a hammer."

I am a mother and a father, but have never given birth. I'm rarely still, but I never wander. What am I?

Tree.

There is one thing that goes round the house and also inside the house but never even share a brief touch. What is it?

Sun.

A black dog stands in the middle of an intersection in a town painted black. None of the street lights are working due to a power failure caused by a storm. A car with two broken headlights drives towards the dog but turns in time to avoid hitting him. How could the driver have seen the dog in time?

It was daylight.

Swaff was traveling in an elevator, being cool, when he suddenly heard the cord supporting the elevator snap. Being the cool guy that he is, he knew of a myth where if you could jump at the right time, you could possibly be able to survive a plunge in an elevator.
Now, when Swaff was a boy, he spent all of his math classes making fun of his female teacher's moustache. He never paid attention, so he was a tad bit slow in his mathematical calculations. He did, however, have a very bizarre talent, in which he could tell the exact speed he was traveling. That came in pretty lucky today.
Swaff knew he was falling at an even rate of 50 miles per hour. When the cord snapped, he was exactly 110 feet above the ground. He knew that he must jump at the right time to have any hopes of surviving.
Now, after doing the math, please tell me when Swaff jumped.

He never did. By the time Swaff figured out that he would have to jump in 1.5 seconds, he would already be dead. Not even the best of mathematicians could do all the math needed in 1 and half seconds. Swaff fell to his death.

Note: This riddle must be done IN YOUR HEAD ONLY and NOT using paper and a pen.
Take 1000 and add 40 to it.
Now add another 1000.
Now add 30.
Another 1000.
Now add 20.
Now add another 1000.
Now add 10.
What is the total?

The answer is 4100, check it out on a calculator. Did you think it was 5000? Most people add the 100 as 1000 by mistake.

Consider the following explanation for why 1=2:
1. Start out Let y = x
2. Multiply through by x xy = x2
3. Subtract y2 from each side xy - y2 = x2 - y2
4. Factor each side y(x-y) = (x+y)(x-y)
5. Divide both sides by (x-y) y = x+y
6. Divide both sides by y y/y = x/y + y/y
7. And so... 1 = x/y + 1
8. Since x=y, x/y = 1 1 = 1 + 1
8. And so... 1 = 2
How is this possible?

Step 5 is invalid, because we are dividing by (x-y), and since x=y, we are thus dividing by 0. This is an invalid mathematical operation (division by 0), and so by not followinng basic mathematical rules, we are able to get strange results like these.