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
Finding The Car Riddle
There are three doors in front of you. New car waits behind one of them; goat is hidden behind each of the remaining two. You may open one of the doors and get what is behind them. You want the car off course. You choose your door. Moderator (who knows where the car is) than opens one of the remaining doors and shows that there is goat. Now he gives you the opportunity to change your decision.
You are standing in front of two closed doors. Will you change your decision?
You are standing in front of two closed doors. Will you change your decision?
Hint: It matters whether you change your decision or not.
Imagine there were one hundred doors and moderator would open all but two.
Its better to change the door.
You win in case you chose wrong door at first (odds 2-in-3).
If you dont change the door you win only in case you originally picked the correct door (1-in-3).
Did you answer this riddle correctly?
YES NO
You win in case you chose wrong door at first (odds 2-in-3).
If you dont change the door you win only in case you originally picked the correct door (1-in-3).
Did you answer this riddle correctly?
YES NO
Finding The Clue Riddle
Hint:
Mail Time Birds Riddle
Hint:
12 Numbers Riddle
Hint:
Find Me In A Bathroom Riddle
Im rectangular but Im not a kitchen table
Im usually made of cotton but Im not a T-shirt
I absorb water but Im not a sponge
Im sometimes used at a beach but Im not a bucket
Im found in a bathroom but Im not a toothbrush.
What is it?
Im usually made of cotton but Im not a T-shirt
I absorb water but Im not a sponge
Im sometimes used at a beach but Im not a bucket
Im found in a bathroom but Im not a toothbrush.
What is it?
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
Find Me In A Palm Tree Riddle
This is a fruit that contains some water
And can provide milk and oil for cooking
If you ever want to see one growing
On a palm tree's where you should be looking
And can provide milk and oil for cooking
If you ever want to see one growing
On a palm tree's where you should be looking
Hint:
Find The Squares
Hint:
30 squares.
Explanation:
Assuming smallest square side is 1 meters, then
Total number of squares with side 1 meters are 16
Total number of squares with side 2 meters are 9
Total number of squares with side 3 meters are 4
Total number of squares with side 4 meters is 1
summing 16+9+4+1 = 30 Did you answer this riddle correctly?
YES NO
Explanation:
Assuming smallest square side is 1 meters, then
Total number of squares with side 1 meters are 16
Total number of squares with side 2 meters are 9
Total number of squares with side 3 meters are 4
Total number of squares with side 4 meters is 1
summing 16+9+4+1 = 30 Did you answer this riddle correctly?
YES NO
Finding Circles
Hint:
17
Explanation:
You can see the center circle right?
There are 16 more circles. Probably you missed them. Just concentrate on the center circle for a moment and you will find the other 16 circles.
Thus there are a total of 17 circles in the given picture. Did you answer this riddle correctly?
YES NO
Explanation:
You can see the center circle right?
There are 16 more circles. Probably you missed them. Just concentrate on the center circle for a moment and you will find the other 16 circles.
Thus there are a total of 17 circles in the given picture. Did you answer this riddle correctly?
YES NO
America's First Clock Riddle
Hint:
Find Me In Your Body
This is found in your body
From your feet up to your head
It is a type of liquid
And it is the color red
What am I?
From your feet up to your head
It is a type of liquid
And it is the color red
What am I?
Hint:
Finding The Dough
Hint:
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