100 Blank Cards Riddle
Someone offers you the following deal:
There is a deck of 100 initially blank cards. The dealer is allowed to write ANY positive integer, one per card, leaving none blank. You are then asked to turn over as many cards as you wish. If the last card you turn over is the highest in the deck, you win; otherwise, you lose.
Winning grants you $50, and losing costs you only the $10 you paid to play.
Would you accept this challenge?
There is a deck of 100 initially blank cards. The dealer is allowed to write ANY positive integer, one per card, leaving none blank. You are then asked to turn over as many cards as you wish. If the last card you turn over is the highest in the deck, you win; otherwise, you lose.
Winning grants you $50, and losing costs you only the $10 you paid to play.
Would you accept this challenge?
Hint: Perhaps thinking in terms of one deck is the wrong approach.
Yes!
A sample strategy:
Divide the deck in half and turn over all lower 50 cards, setting aside the highest number you find. Then turn over the other 50 cards, one by one, until you reach a number that is higher than the card you set aside: this is your chosen "high card."
Now, there is a 50% chance that the highest card is contained in the top 50 cards (it is or it isn't), and a 50% chance that the second-highest card is contained in the lower 50. Combining the probabilities, you have a 25% chance of constructing the above situation (in which you win every time).
This means that you'll lose three out of four games, but for every four games played, you pay $40 while you win one game and $50. Your net profit every four games is $10.
Obviously, you have to have at least $40 to start in order to apply this strategy effectively. Did you answer this riddle correctly?
YES NO
A sample strategy:
Divide the deck in half and turn over all lower 50 cards, setting aside the highest number you find. Then turn over the other 50 cards, one by one, until you reach a number that is higher than the card you set aside: this is your chosen "high card."
Now, there is a 50% chance that the highest card is contained in the top 50 cards (it is or it isn't), and a 50% chance that the second-highest card is contained in the lower 50. Combining the probabilities, you have a 25% chance of constructing the above situation (in which you win every time).
This means that you'll lose three out of four games, but for every four games played, you pay $40 while you win one game and $50. Your net profit every four games is $10.
Obviously, you have to have at least $40 to start in order to apply this strategy effectively. Did you answer this riddle correctly?
YES NO
Mermaids New House Riddle
Hint:
It Has Got A Car But No Wheels
Hint:
Spider Car Riddle
Hint:
A Little House Riddle
Hint:
Goes With A Car Riddle
Hint:
If A Red House Is Made From Red Bricks Riddle
Hint:
A Man Pushes His Car
Hint:
A Man Is Pushing His Car Along The Road Riddle
Hint:
What Comes Into A House Through The Keyhole Riddle
Hint:
Carpenter Nails Riddle
Hint:
The Hijacker Riddle
A man hijacks an airplane transporting both passengers(8 of them) and valuable cargo. After taking the cargo, the man demands nine parachutes, puts one of them on, and jumps, leaving the other eight behind. Why did he want eight?
Hint:
If the officials thought he was jumping with a hostage, they would never risk giving him a faulty parachute. Did you answer this riddle correctly?
YES NO
YES NO
My House Is With Me
I have four legs and a tail.
I have no teeth.
I can swim and dive underwater.
I carry my house around with me.
I am a...
I have no teeth.
I can swim and dive underwater.
I carry my house around with me.
I am a...
Hint:
Guilders Expense Riddle
While building a medieval cathedral, it cost 37 guilders to hire 4 artists and 3 stonemasons or 33 guilders for 3 artists and 4 stonemasons. What would the expense of just one of each?
Hint:
Ten guilders. An artist cost 7 guilders, and a stonemason cost 3 guilders.
Did you answer this riddle correctly?
YES NO
Did you answer this riddle correctly?
YES NO
Bigger Than A Car Riddle
I go very far, so there's no need to push.
Bigger than a car, yet can hide in a bush.
They say I go round and round, like a top.
I move on the ground until I reach a stop.
What am I?
Bigger than a car, yet can hide in a bush.
They say I go round and round, like a top.
I move on the ground until I reach a stop.
What am I?
Hint:
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