100 Offices Riddle
A new medical building containing 100 offices had just been completed. Mark was hired to paint the numbers 1 to 100 on the doors. How many times will Mark have to paint the number nine?
Hint:
Did you say three? The correct answer is twenty (29, 39, and so on). Did you answer this riddle correctly?
YES NO
YES NO
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:
The Traffic Light Riddle
There is a traffic light at the top of a hill. Cars can't see the light until they are 200 feet from the light.
The cycle of the traffic light is 30 seconds green, 5 seconds yellow and 20 seconds red.
A car is traveling 45 miles per hour up the hill.
What is the probability that the light will be yellow when the driver first crests the hill and that if the driver continues through the intersection at her present speed that she will run a red light?
The cycle of the traffic light is 30 seconds green, 5 seconds yellow and 20 seconds red.
A car is traveling 45 miles per hour up the hill.
What is the probability that the light will be yellow when the driver first crests the hill and that if the driver continues through the intersection at her present speed that she will run a red light?
Hint:
The probability of the driver encountering a yellow light and the light turning red before the car enters the intersection is about 5.5%.
At 45 mph the car is traveling at 66 feet/second and will take just over 3 seconds (3.03) to travel the 200 feet to the intersection. Any yellow light that is in the last 3.03 seconds of the light will cause the driver to run a red light.
The entire cycle of the light is 55 seconds. 3.03/55 = 5.5%. Did you answer this riddle correctly?
YES NO
At 45 mph the car is traveling at 66 feet/second and will take just over 3 seconds (3.03) to travel the 200 feet to the intersection. Any yellow light that is in the last 3.03 seconds of the light will cause the driver to run a red light.
The entire cycle of the light is 55 seconds. 3.03/55 = 5.5%. Did you answer this riddle correctly?
YES NO
Charging For Venison Riddle
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Noah's Lights Riddle
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A Vegetarian Zombie Riddle
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Light Me Up For A Sprinkle Of Gold Riddle
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Christmas Vehicular Homicide Riddle
Vehicular homicide was committed on Dad's mom by a precipitous darlin, what Christmas Carol is this?
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
Five Rows Of Four Christmas Trees Riddle
Hint:
Just imagine a 5 pointed star, and then plant one tree at each point, and one tree where the sides intersect.
There are actually several distinct solutions. All of them can be constructed as follows:
Draw a nice long straight line.
Draw a second straight line that intersects the first.
Draw three more straight lines making sure each line intersects all the lines youve already drawn and avoiding any of the previous points of intersection. That is, no three lines should intersect at the same point.
With the first four lines, theres only one topologically distinct configuration, but by varying the position of the fifth line, several different distinct configurations can be created. Did you answer this riddle correctly?
YES NO
There are actually several distinct solutions. All of them can be constructed as follows:
Draw a nice long straight line.
Draw a second straight line that intersects the first.
Draw three more straight lines making sure each line intersects all the lines youve already drawn and avoiding any of the previous points of intersection. That is, no three lines should intersect at the same point.
With the first four lines, theres only one topologically distinct configuration, but by varying the position of the fifth line, several different distinct configurations can be created. Did you answer this riddle correctly?
YES NO
Garland, Lights And Balls Riddle
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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
Lighter Than Air Riddle
Hint:
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