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
Bad Grades Firefly Riddle
Hint:
A Blind Girl Lost Her Pencil Riddle
Hint:
I Have Two Arms But Fingers None Riddle
I have two arms, but fingers none. I have two feet, but cannot run. I carry well, but I have found I carry best with my feet off the ground. What am I?
Hint:
A Zombie A Mummy And A Ghost Bought A House Riddle
A zombie, a mummy, and a ghost bought a house. It has all of the usual rooms except for one. What room won't you find?
Hint:
Go To Where You Find News Of June Riddle
Go to where you find news of June. Her exploits and her fate. There is an image posted there, on this calendar date. The password that you need is what is depicted there. So name it and you have your code. Surely that is fair
Hint:
Find That Tennis Ball
You have 7 tennis balls that are all identical but one of them is slightly lighter than the others.
Using a balance scale and only two separate weightings, how can you find the light tennis ball?
Using a balance scale and only two separate weightings, how can you find the light tennis ball?
Hint:
Put three of the balls on each side. If they are even the ball that wasn't weighed is the light one. If they aren't even the side that is lighter has the light ball. Of these three balls, one should be put on each side. If the sides are even than the other ball is the light one. If they aren't even the one that is lighter is the ball you're looking for. Did you answer this riddle correctly?
YES NO
YES NO
Without Me You Would Be Lost
I guide you but you can't hear me. Without me you would be lost. I keep going and won't be stopped. What am I?
Hint:
Carrying Trees
Hint:
Fighting For Hours
Thirty men and only two women, but they hold the most power. Dressed in black and white, they could fight for hours. Who are they?
Hint: They live on a board. You are their lord.
The Old Horror House
There is an old horror house. It has no electricity, plumbing, or power of any sort. You go inside and see three doors. Each door has a number on it. In each door is a way for you to die. In door number one, you die by getting eaten by a lion. In door number two, you die by getting murdered. In door number three, you die by electric chair. You may not turn back so you have to go through a door.
Which door do you go through?
Which door do you go through?
Hint:
Go through number three. You'll survive because it's an electric chair and there is no electricity. Did you answer this riddle correctly?
YES NO
YES NO
Mother's Day Cards
Hint:
Flying House Riddle
Hint:
Higher Than A House
Hint:
The Exam Cheater Riddle
Hint:
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