Rope Burn Riddle
You have two ropes. Each rope takes one hour to burn. These ropes are not identical, nor are they uniform; i.e. it does not necessarily take half an hour for half the rope to burn (if you have trouble visualizing this, imagine a rope of varying thickness across its length). With only these two ropes and a way to light them, how do you measure out 45 minutes?
Hint: You can light multiple ends and/or multiple ropes at the exact same time.
Light both ends of one rope, and only one end of the other rope. This will cause the first rope to burn out in 30 minutes. When the first rope burns out, there will be 30 minutes left on the second rope. So then, light the other end of the second rope, and the rest of it will burn out in 15 minutes. 30 + 15 = 45 minutes. Did you answer this riddle correctly?
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YES NO
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?
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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
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100 Lbs Riddle
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School Ladder Riddle
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Stressed Out Rope Riddle
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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?
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YES NO
Steals $100 Riddle
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Hangs On The Wall And Falls Riddle
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My Life Hangs By A Thread Riddle
I have joy in bringing two together, but darning my existence! My life hangs by a thread, filled with ups, downs and resistance! I am a?
Hint:
You Start With 1000 Riddle
You start with 1000 then add 40 add another 1000 then add 30 add another 1000 then add 20 add one more 1000 then add 10 what is your answer?
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?
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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
How Many 9 In 100 Riddle
Hint:
There are total 20 nine's between 1 and 100. 9, 19, 29, 39, 49, 59, 69, 79, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99. you can count total 9 in these series. Did you answer this riddle correctly?
YES NO
YES NO
How Many 7s Are Between 0 100 Riddle
Hint:
The answer is 20
7, 17, 27, 37, 47, 57 ,67, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 87, 97 Did you answer this riddle correctly?
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7, 17, 27, 37, 47, 57 ,67, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 87, 97 Did you answer this riddle correctly?
YES NO
Behind Where It Hangs It Hides Riddle
Hint:
A Barometer.
A barometer is a scientific instrument that is used to measure air pressure in a certain environment. Many measurements of air pressure are used within surface weather analysis to help find surface troughs, pressure systems and frontal boundaries.
A barometer measures air pressure: A "rising" barometer indicates increasing air pressure; a "falling" barometer indicates decreasing air pressure...Therefore, on any given day you would expect the air over a desert to have a lower pressure than the air over an ice cap. Did you answer this riddle correctly?
YES NO
A barometer is a scientific instrument that is used to measure air pressure in a certain environment. Many measurements of air pressure are used within surface weather analysis to help find surface troughs, pressure systems and frontal boundaries.
A barometer measures air pressure: A "rising" barometer indicates increasing air pressure; a "falling" barometer indicates decreasing air pressure...Therefore, on any given day you would expect the air over a desert to have a lower pressure than the air over an ice cap. Did you answer this riddle correctly?
YES NO
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