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
10 From 100 Riddle
Hint:
100 Lbs Riddle
Hint:
The Sick Ship Riddle
Hint:
The Number Four Be Half Of Five Riddle
Hint:
IV, the Roman numeral for four, which is “half” (two letters) of the word five. Did you answer this riddle correctly?
YES NO
YES NO
1500 Plus 20 And 1600 Minus 40 Riddle
Hint:
The Same Problem Riddle
Hint:
Who Stole The $100,000 Riddle
A man leaves a $100,000 dollar bill on his desk and leaves work. When he returns the money is gone. He has three suspects: the cook, the cleaning lady, and the mail guy. The cook says he put the money under a book on his desk to keep it safe. They check and it is no longer there. The maid says she moved it when she was cleaning to the inside of the book between page 1 and 2. They open the book and look between page number 1 and 2 but it isn't there. The mail guy says he saw it sticking out of the book and to keep it safe he moved it to between page number 2 and 3. Once they are done the culprit is promptly arrested. Who did it and how did he know?
Hint:
The mail guy did it because if he checked between page numbers 1 and 2 page numbers 2 and 3 are opposite sides of one page and could not hold the dollar bill. Did you answer this riddle correctly?
YES NO
YES NO
Half A Tomato Riddle
Hint:
Half A Lemon Riddle
Hint:
Born In 1995 Riddle
Hint:
He was born in Hospital room '1995' but he died in the year of 1953. Did you answer this riddle correctly?
YES NO
YES NO
Steals $100 Riddle
Hint:
You Start With 1000 Riddle
Hint:
If you said 5000 you're wrong! The answer is 4100, how?
1000 + 40 = 1040
1040 + 1000 + 30 = 2070
2070 + 1000 + 20 = 3090
3090 + 1000 = 4090
4090 + 10 = 4100 Did you answer this riddle correctly?
YES NO
1000 + 40 = 1040
1040 + 1000 + 30 = 2070
2070 + 1000 + 20 = 3090
3090 + 1000 = 4090
4090 + 10 = 4100 Did you answer this riddle correctly?
YES NO
I Had A Sister Half My Age Riddle
Hint:
When you were 6 your sister was 6/2 = 3.
Now that you are 70 your sister is 70-3 = 67 Did you answer this riddle correctly?
YES NO
Now that you are 70 your sister is 70-3 = 67 Did you answer this riddle correctly?
YES NO
Frank Was Born In 1933 Riddle
Hint:
He was born in the hospital room 1933 and died in room 1946. Did you answer this riddle correctly?
YES NO
YES NO
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