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
Many Things Can Be Played Riddle
If youre bored and have a set of these
There are many things that can be played
Each has a number, letter or head
And a diamond, club, heart or a spade
What is it?
There are many things that can be played
Each has a number, letter or head
And a diamond, club, heart or a spade
What is it?
Hint:
The Best Place For Ice Cream
Hint:
Hands That Don't Hold Riddle
Hands she has but does not hold, teeth she has but does not bite, feet she has but they are cold, eyes she has but without sight. Who is she?
Hint:
Up And Down At The Same Time
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:
Interacting With All Living Things
Hint:
Flying With Both Hands Riddle
Why does superman fly with one hand at the side and one hand pointing straight ahead in the past, but now he flies with both hands pointing straight ahead?
Hint:
In the past, Superman was on manual mode but now he's on autopilot mode. Did you answer this riddle correctly?
YES NO
YES NO
Time And Commitment Riddle
With time and commitment you will find this.
And learning to have it alleviates stress in your life.
What is it?
And learning to have it alleviates stress in your life.
What is it?
Hint:
In Times Of War Riddle
Hint:
12 Numbers Riddle
Hint:
Around You All The Time Riddle
Hint:
The Nurses Office Riddle
Hint:
Angry Mother Needle Riddle
Hint:
Just Use Your Hands Riddle
What four-letter word begins with f and ends with k, and if you cant get it you can always just use your hands?
Hint:
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