Hard Brain Teasers for Adults Who Crave a Challenge

You see a boat filled with people, yet not a single person is on board. How?

A farmer has seventeen sheep. All but nine run away. How many are left?

I speak without a mouth and hear without ears. I have no body, but I come alive with wind. What am I?

The person who makes it, sells it. The person who buys it never uses it. The person who uses it never knows. What is it?

You measure my life in hours and I serve you by expiring. I am quick when I am thin and slow when I am fat. What am I?

A man runs to the airport, arrives exactly on time, yet his plane leaves without him. Why?

A prison warden tells a prisoner: say a true sentence and you will be hanged; say a false sentence and you will be shot. What can the prisoner say to survive?

I am the beginning of everything, the end of everywhere, the beginning of eternity, and the end of time. What am I?

You enter a room with a match, a candle, a furnace, and a gas lamp. Which do you light first?

What flies without wings and falls without touching the ground?

Two mothers and two daughters go shopping. They buy three pairs of shoes but everyone gets a pair. How?

I am taken from a mine and shut up in a wooden case, from which I am never released, and yet I am used by almost everyone. What am I?

Take away the whole and some still remains. What is it?

A man looks at a painting and says, “Brothers and sisters I have none, but that man's father is my father's son.” Who is in the painting?

What loses its head in the morning but gets it back at night?

You have nine identical-looking balls. One is heavier. Using a balance scale only twice, how do you find the heavy ball?

A bat and a ball cost $1.10 together. The bat costs $1.00 more than the ball. How much does the ball cost?

You have two U.S. coins that total thirty cents. One of them is not a nickel. What are the coins?

If all bloops are razzles, and all razzles are lazzles, must all bloops be lazzles?

How can the number four be half of five?

How many months of the year have twenty-eight days?

A truck driver goes the wrong way down a one-way street. Several police officers see it and do nothing. Why?

Before Mount Everest was discovered, what was the highest mountain on Earth?

How many animals of each kind did Moses take on the ark?

A man rode into town on Tuesday, stayed three days, and left on Tuesday. How?

A man pushes his car up to a hotel door and immediately knows he is bankrupt. What happened?

A father and son are in a car crash. The father dies. The son is rushed to surgery. The surgeon says, “I cannot operate, this is my son.” How?

A man lives on the tenth floor. Every day he takes the elevator down. When he returns, he rides to the seventh floor and walks the rest, unless it is raining. On rainy days he rides all the way up. Why?

How far can a dog run into the woods?

What can you hold in your right hand but not in your left hand?

I have no life, but I can die. What am I?

What five-letter word becomes shorter when you add two letters to it?

What word is spelled incorrectly in every dictionary?

What has many keys but cannot open a single lock?

If you throw a blue stone into the Red Sea, what happens to the stone?