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 House With No Doors Riddle
Hint:
A fish. A fish bowl or aquarium is the fishs house and the people inside are the decorative divers that offer no reply (one might ask how the fish knows, given that they arent a talkative bunch themselves). Did you answer this riddle correctly?
YES NO
YES NO
Here To Make You Happy
I look pretty and I am sweet
but still people like to reap me.
I am soft sometimes but still
people use razor knife to cut me
I am here to give you joy
but still people put fire on me
I am here to make you happy
but people use me to smear others face.
So what am I?
but still people like to reap me.
I am soft sometimes but still
people use razor knife to cut me
I am here to give you joy
but still people put fire on me
I am here to make you happy
but people use me to smear others face.
So what am I?
Hint:
I Never Was But Always Will Be Riddle
I never was but always will be. No one ever saw me but everyone knows I exist. I give people the motivation to better themselves everyday. What am I?
Hint:
Positive Numbers
Hint:
The Same Birthday
How many people do you need to have the odds be in favor (at least 50% chance) of two people having the same birthday?
Hint:
Brownie Currency
You're going to a friends house and want to give them some brownies. On the way to their house you cross 5 bridges. At each bridge you must pay a toll of half of your brownies to the owner. But they are all very nice and give you back a brownie from what you give them.
How many brownies must you start with to give your friend 2 brownies?
How many brownies must you start with to give your friend 2 brownies?
Hint:
Just 2.
Each time you give the owner of a bridge half of your brownies (1 brownie) they give you one back as well. Did you answer this riddle correctly?
YES NO
Each time you give the owner of a bridge half of your brownies (1 brownie) they give you one back as well. Did you answer this riddle correctly?
YES NO
I Have Three Eyes
I stare at you, you stare at me. I have three eyes, yet can't see. Every time I blink, I give you commands. You do as you are told, with your feet and hands. What am I?
Hint:
Skipping The Pop Quiz
A teacher decides to give a pop quiz one day but all of her students refuse to take the quiz thinking that the teacher will call off the quiz. She can give only one of these students a detention for skipping the quiz. All of the students know each other's names and if a student knows he/she is getting a detention they take the quiz.
How can she threaten her students with the single detention so they all take the quiz?
How can she threaten her students with the single detention so they all take the quiz?
Hint:
She tells them that she will give the student who skips the quiz whose name comes first alphabetically a detention. This student won't skip because they know they are getting a detention if they do. The next person alphabetically will then know that they will get a detention so they won't skip either, and so on. Did you answer this riddle correctly?
YES NO
YES NO
One Sick Horse
Hint:
All I Do Is Wander And Devour
I'm tall and I'm skinny, and yet very shy.
I live just an hour then, as quickly, I die.
All that I do in my one given hour
is wander a trail and all things devour.
When e'er people see me, they never are glad,
but when I depart them, they're never more sad.
I live just an hour then, as quickly, I die.
All that I do in my one given hour
is wander a trail and all things devour.
When e'er people see me, they never are glad,
but when I depart them, they're never more sad.
Hint:
Bus Driver Eyes
Hint:
The eye color of the reader of this problem. The first sentence is the key: "You are the bus driver". Did you answer this riddle correctly?
YES NO
YES NO
The Death Lift Riddle
A lift is on the ground floor. There are 4 people in the lift including me.
When the lift reaches 1st floor, 1 person gets out 3 people get in.
The lift goes up to the second floor, 2 people get out 6 people get in.
It then goes up to the next floor up, no-one gets out but 12 people get in. Halfway up to the next floor up the lift cable snaps, it crashes to the floor. Everyone dies in the lift. How did I survive?
When the lift reaches 1st floor, 1 person gets out 3 people get in.
The lift goes up to the second floor, 2 people get out 6 people get in.
It then goes up to the next floor up, no-one gets out but 12 people get in. Halfway up to the next floor up the lift cable snaps, it crashes to the floor. Everyone dies in the lift. How did I survive?
Hint:
Losing Sleep Riddle
Hint:
Sharing Apples Riddle
Hint:
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