Dangerous Chemicals Riddle
There is a chemical that is very dangerous. If this chemical is inhaled, it may be fatal. Under certain conditions, contact with the skin can cause a burn. However, once a person's body becomes dependent on this chemical, prolonged separation from this chemical can cause death. However, even though many people know of this chemical, and it is found in nearly every drinking source, nothing is being done to try to get rid of it. Why is nothing being done about this chemical?
Hint: This is a real chemical. Think about everything that is being said.
No one does anything about it because the chemical is water. Did you answer this riddle correctly?
YES NO
YES NO
Outrunning A Train Riddle
Walking home one day, you take a short cut along the train tracks. The tracks cross a narrow bridge over a deep gorge. At the point you are 3/8 of the way across the bridge, you hear the train whistle somewhere behind you. You charge across the bridge, and jump off the track as the train is about to run you down. As it happens, if you had gone the other way, you would have reached safety just before being run over as well. If you can run ten miles per hour, how fast is the train moving?
Hint:
The train is moving at 40 miles per hour. Imagine that a friend is walking with you. When the train whistle blows, you head away from the train, he heads toward it. When he reaches safety, you will be 6/8 (or 3/4)of the way across the bridge, and the train will have just reached the bridge. For the train to cross 4/4 of the bridge in the time you cross the remaining 1/4, the train must be moving four times your speed. Did you answer this riddle correctly?
YES NO
YES NO
The Nonstop Trains Riddle
A nonstop train leaves Moscow for Leningrad at 60 mph. Another nonstop train leaves leningrad for Moscow at 40 mph. How far apart are the trains 1 hour before they pass each other?
Hint:
Dreams Of Guillotines Riddle
A lawyer argued for $1,000,000 damages based on the following claim: His client went to an art museum, where he saw a painting of Marie Antoinette on a guillotine. He fell asleep and dreamed of the painting. At the museums closing time, a guard tapped him on the neck just as he dreamed of the guillotine beheading Marie Antoinette. The tap provoked immediate cardiac arrest and a fatal heart attack immediately following, because he associated the tap with the guillotine blade.
The judge dismissed the case. Why?
The judge dismissed the case. Why?
Hint:
If the client died in his sleep, there would be no way of knowing what he was dreaming. Did you answer this riddle correctly?
YES NO
YES NO
Flip The Switch Riddle
There is a prison with 100 prisoners, each in separate cells with no form of contact. There is an area in the prison with a single light bulb in it. Each day, the warden picks one of the prisoners at random, even if they have been picked before, and takes them out to the lobby. The prisoner will have the choice to flip the switch if they want. The light bulb starts off.
When a prisoner is taken into the area with the light bulb, he can also say "Every prisoner has been brought to the light bulb." If this is true all prisoners will go free. However, if a prisoner chooses to say this and it's wrong, all the prisoners will be executed. So a prisoner should only say this if he knows it is true for sure.
Before the first day of this process begins, all the prisoners are allowed to get together to discuss a strategy to eventually save themselves.
What strategy could they use to ensure they will go free?
When a prisoner is taken into the area with the light bulb, he can also say "Every prisoner has been brought to the light bulb." If this is true all prisoners will go free. However, if a prisoner chooses to say this and it's wrong, all the prisoners will be executed. So a prisoner should only say this if he knows it is true for sure.
Before the first day of this process begins, all the prisoners are allowed to get together to discuss a strategy to eventually save themselves.
What strategy could they use to ensure they will go free?
Hint:
Only allow one prisoner to turn the light bulb off and all of the others turn it on if they have never turned it on before. If they have turned it on before they do nothing. The prisoner that can turn it off then knows they have all been there and saves them all when he has turned it off 99 times. Did you answer this riddle correctly?
YES NO
YES NO
100 Widgets Riddle
If it takes 5 machines 5 minutes to make 5 widgets, how long would it take 100 machines to make 100 widgets?
Hint:
It would take 5 minutes. Each machine takes 5 minutes to make its widget. Therefore, each of the 100 machines would have finished making its widget in 5 minutes. Did you answer this riddle correctly?
YES NO
YES NO
A Special Integer Riddle
A special integer exists in mathematics that shows a special property. If you subtract any number from that integer, the result will always be divisible by the successor of that number completely.
Do you know what that integer is ?
Do you know what that integer is ?
Hint:
The required integer is -1.
For an example, let us subtract 7 from -1.
-1 - 7 = -8
Now the successor of 7 is 8 and (-8) is exactly divisible by 8.
You can try that for any number and it will hold true. Did you answer this riddle correctly?
YES NO
For an example, let us subtract 7 from -1.
-1 - 7 = -8
Now the successor of 7 is 8 and (-8) is exactly divisible by 8.
You can try that for any number and it will hold true. Did you answer this riddle correctly?
YES NO
Two Fathers Two Sons Riddle
There are two fathers and two sons going on a fishing trip. Every person catches one fish. In total, there were only 3 fish. How is that so?
Hint:
A Rickety Bridge Riddle
Four people need to cross a rickety bridge at night. Unfortunately, they have only one torch and the bridge is too dangerous to cross without one. The bridge is only strong enough to support two people at a time. Not all people take the same time to cross the bridge. Times for each person: 1 min, 2 mins, 7 mins and 10 mins. What is the shortest time needed for all four of them to cross the bridge?
Hint:
17 mins.
The initial solution most people will think of is to use the fastest person as an usher to guide everyone across. How long would that take? 10 + 1 + 7 + 1 + 2 = 21 mins. Is that it? No. That would make this question too simple even as a warm up question.
Let's brainstorm a little further. To reduce the amount of time, we should find a way for 10 and 7 to go together. If they cross together, then we need one of them to come back to get the others. That would not be ideal. How do we get around that? Maybe we can have 1 waiting on the other side to bring the torch back. Ahaa, we are getting closer. The fastest way to get 1 across and be back is to use 2 to usher 1 across. So let's put all this together.
1 and 2 go cross
2 comes back
7 and 10 go across
1 comes back
1 and 2 go across (done)
Total time = 2 + 2 + 10 + 1 + 2 = 17 mins Did you answer this riddle correctly?
YES NO
The initial solution most people will think of is to use the fastest person as an usher to guide everyone across. How long would that take? 10 + 1 + 7 + 1 + 2 = 21 mins. Is that it? No. That would make this question too simple even as a warm up question.
Let's brainstorm a little further. To reduce the amount of time, we should find a way for 10 and 7 to go together. If they cross together, then we need one of them to come back to get the others. That would not be ideal. How do we get around that? Maybe we can have 1 waiting on the other side to bring the torch back. Ahaa, we are getting closer. The fastest way to get 1 across and be back is to use 2 to usher 1 across. So let's put all this together.
1 and 2 go cross
2 comes back
7 and 10 go across
1 comes back
1 and 2 go across (done)
Total time = 2 + 2 + 10 + 1 + 2 = 17 mins Did you answer this riddle correctly?
YES NO
The Perfect Pill Riddle
The world is facing a serious viral infection. The government of various countries have issued every citizen two bottles. You as well have been given the same. Now one pill from each bottle is to be taken every day for a month to become immune to the virus. The problem is that if you take just one, or if you take two from the same bottle, you will die a painful death.
While using it, you hurriedly open the bottles and pour the tablets in your hand. Three tablets come down in your hand and you realize they look exactly the same and have same characteristics. You cant throw away the pill as they are limited and you cant put them back or you may put it wrong and may die someday.
How will you ensure that you are taking the right pill?
While using it, you hurriedly open the bottles and pour the tablets in your hand. Three tablets come down in your hand and you realize they look exactly the same and have same characteristics. You cant throw away the pill as they are limited and you cant put them back or you may put it wrong and may die someday.
How will you ensure that you are taking the right pill?
Hint:
You must put labels on the tablets as A and B before using. In that case, if you pour tablets together, you will get 3A, 2A 1B, 1A 2B or 3B. If they are from the same bottles you can take one from another bottle and save the remaining two for another day. If you get two from same and one from other, you can draw one from another bottle and you will have two pairs of which you can eat one and save the other. Did you answer this riddle correctly?
YES NO
YES NO
Person In The Painting Riddle
A man walks into an art gallery and concentrates on one picture in particular. The museum curator notices this and asks the man why he is so interested in that one painting. The man replies, "Brothers and sisters have I none, but that man's father is my father's son."
Who is in the painting?
Who is in the painting?
Hint:
The Non Digital Clock Riddle
Calculate the number of degrees between the hour hand and the minute hand of a clock (nondigital) that reads 3:15.
Hint:
The hour hand will have moved one-fourth of an hour; therefore, there will be 7.5 degrees between the two hands. Did you answer this riddle correctly?
YES NO
YES NO
The Best Thing About Winter
The best thing about winter
Is when outdoors you go
And have a fight with your friends
Using balls made out of...?
Is when outdoors you go
And have a fight with your friends
Using balls made out of...?
Hint:
IQ Of 50 Riddle
Hint:
Paper Threes Riddle
Jenna wrote all the numbers from 300 to 400 on a piece of paper. How many times did she write the digit 3?
Hint:
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