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
A Time To Travel Riddle
Hint:
Crossing The Bridge Riddle
There are two villages separated with a river. Each day, four people cross the river through a bridge to work on the other side and earn for their families. On one night when they were returning from work, they noticed that the bridge was about to collapse. Now all of them wanted to cross the bridge before it collapsed as no one wanted to be stuck on that end without their families.
They had just one torch with them and since it was the night time, they could not see without it. The bridge had become weak and it could only accommodate two people at a time. It was going to collapse in just 17 minutes.
The four people took different times to cross the bridge. First one took only a minute, second one took 2 minutes, third one took 5 minutes and the last one took 10 minutes.
How would all of them have managed to cross the bridge in time?
They had just one torch with them and since it was the night time, they could not see without it. The bridge had become weak and it could only accommodate two people at a time. It was going to collapse in just 17 minutes.
The four people took different times to cross the bridge. First one took only a minute, second one took 2 minutes, third one took 5 minutes and the last one took 10 minutes.
How would all of them have managed to cross the bridge in time?
Hint:
Let us denote the four people with A, B, C and D.
A takes 1 minute to cross, B takes 2, C takes 5 and D takes 10.
A and B cross first spending 2 minutes.
A comes back with torch taking 1 minute.
C and D cross taking 10 minutes.
B comes back with torch taking 2 minutes.
Finally, A and B cross the bridge taking 2 minutes.
2 + 1 + 10 + 2 + 2 = 17 minutes
Thus, this is the way they all managed to cross that bridge that night. Did you answer this riddle correctly?
YES NO
A takes 1 minute to cross, B takes 2, C takes 5 and D takes 10.
A and B cross first spending 2 minutes.
A comes back with torch taking 1 minute.
C and D cross taking 10 minutes.
B comes back with torch taking 2 minutes.
Finally, A and B cross the bridge taking 2 minutes.
2 + 1 + 10 + 2 + 2 = 17 minutes
Thus, this is the way they all managed to cross that bridge that night. Did you answer this riddle correctly?
YES NO
True Bravery Riddle
Hint:
Like A Flower Riddle
Hint:
747 Humps Riddle
Hint:
Four Countries Riddle
The letters ACDEHIJLNP can be used to spell out the names of four countries. Each name is five letters long, and the four countries are be neighbors. What are the countries?
Hint:
Digits From 1 To 9 Riddle
Hint:
Next In The Sequence Riddle
Hint:
N. The letter represent the first letters of the months of the year, starting with March. N is for November, and of course D would be the next one. Did you answer this riddle correctly?
YES NO
YES NO
12 Numbers Riddle
Hint:
Running Watches Riddle
I started 2 watches at the same time,
It turned out that one of them went two minutes per hour too slow,
and the other went one minute per hour too fast.
When I looked at them again,
the faster one was exactly one hour ahead of the other.
How long had the watches been running?
It turned out that one of them went two minutes per hour too slow,
and the other went one minute per hour too fast.
When I looked at them again,
the faster one was exactly one hour ahead of the other.
How long had the watches been running?
Hint:
The faster watch gains on the slower one at the rate of three minutes every hour. After 20 hours, the faster one will be ahead by one hour. Did you answer this riddle correctly?
YES NO
YES NO
What Word Starts With E And End With E
Hint: Letter is a dead give away
The Falling Lady Riddle
A football player is running to get a net under a lady who looks like she might jump off the balcony of her 20 story apartment building. There is nothing below her except a 20 story fall. The player is still 100 yards away when she falls and can't nearly get there in time. The woman is not hurt more than a bruise. How is that possible?
Hint:
Blowing In The Trees Riddle
I can be very strong
But other times Im just a breeze
Although you cant see me
You can see me blow about trees
What am I?
But other times Im just a breeze
Although you cant see me
You can see me blow about trees
What am I?
Hint:
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Hint:
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