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
Secretes You Can Keep Riddle
Riddle me this
You write on me and secrets I can keep. In places never seen. I spin like a top. Though stiff as a board, I'm often described like a mop. What am I?
You write on me and secrets I can keep. In places never seen. I spin like a top. Though stiff as a board, I'm often described like a mop. What am I?
Hint:
Shapes And Sizes Riddle
Riddle me this
I come in different shapes and sizes. Part of me are curves, others are straight. You can put me anywhere you like, but there is only one right place for me.
What am I?
I come in different shapes and sizes. Part of me are curves, others are straight. You can put me anywhere you like, but there is only one right place for me.
What am I?
Hint:
Growing On Trees Riddle
Hint:
Running Without Getting Tired
I can run constantly without ever getting tired. When I run, I frustrate people and drive them crazy, Yet I don't even have to move to irritate you.
What am I?
What am I?
Hint:
Perfect For Vacation Riddle
South of the Unite States border I reside
Hop upon a burro for a mountain ride
I am known for my food, music, and beaches too
I am the perfect place for a vacation or two
What am I?
Hop upon a burro for a mountain ride
I am known for my food, music, and beaches too
I am the perfect place for a vacation or two
What am I?
Hint:
Half Magic Riddle
There was once a girl who was always jealous of her sister. One day a genie appeared and told her that he was "half magic" which meant that he could grant her wishes, but her sister would always get two times more than she did. She had three wishes. First, she wishes that she was the richest person in the world, but her sister soon became the richest because she got two times the money. Her second wish was that she was the most beautiful woman in the world, but her sister gets twice as much beauty.
What was her third wish?
What was her third wish?
Hint:
She asks the genie to grab a nearby stick and beat her half to death. Did you answer this riddle correctly?
YES NO
YES NO
Marathon Runner Calls Riddle
Hint:
Chewing Whales Riddle
Hint:
12 Numbers Riddle
Hint:
Two Trees Riddle
Hint:
The Arrested Belt Riddle
Hint:
Catching A Fish Riddle
Hint:
Shocked Into Silence Riddle
Hint:
Carrying Children Riddle
Hint:
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