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
Train To Cuba Riddle
If one train in New York is going 1206 mph and one in Florida goes 305 mph which one will get to Cuba first?
Hint:
Too Many Photos Riddle
Jack is taking a tour through a museum's American Presidents exhibit. The person leading the tour tells him "We have a picture of each presidency. Currently Barack Obama is the 43rd person to hold the office." But Jack quickly realizes that there are 44 pictures on the wall. But while walking through the exhibit he realizes why this is.
Why is there one too many photos?
Why is there one too many photos?
Hint:
One president served non-consecutive terms (there was a president between his terms) so he held two different presidencies. The president who really did this was Grover Cleveland. Did you answer this riddle correctly?
YES NO
YES NO
Democrats And Republicans Riddle
Hint:
The Heist Riddle
What was the idea ?
Hint:
Vin Diesel told him to use one nut from each of the other wheels. Did you answer this riddle correctly?
YES NO
YES NO
The Paper Clip And Magnet Riddle
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Gender Of A Chromosome
Hint:
The Detective Trap Riddle
Detective Sara Dunts was called in for an investigation on a Saturday morning. Mr. John Gooding had mysteriously vanished from his one story home, Sara was told. "I'll phone Mrs. Glen, the caretaker, and get you the address." Detective Chad Sandlers, Sara's partner, said. Sara stood waiting as he made the call. "Okay, everything's set. Mrs. Glen will be expecting you in half an hour at 232 Parker At." Detective Chad said.
Sara hopped out of her car and walked up the long path that led to the house. Right away she was ushered inside by Mrs. Glen. "Detective, I'm so glad you came. The last place I saw Mr. Gooding was in his room. I suspected that would be your first question." Mrs. Glen said somewhat nervously. She walked Sara into the other room. "Up here," Mrs. Glen called from a twisting flight of stairs. The front door banged shut just as Sara started up the steps. "Oh, I must have left the door open. The wind must have shut it." Mrs. Glen said. Again they started up the stairs.
They walked up the enormous stairway. Halfway up detective Sara noticed a weather vane through the window. She realized that the wind was blowing west and in order for it to have shut the door it would have to have been blowing east. Then Sara realized for the first time that there was a third set of footsteps on the stairs. Then it dawned on her and she realized she had walked into a trap. How did Sara know she had walked into a trap?
Sara hopped out of her car and walked up the long path that led to the house. Right away she was ushered inside by Mrs. Glen. "Detective, I'm so glad you came. The last place I saw Mr. Gooding was in his room. I suspected that would be your first question." Mrs. Glen said somewhat nervously. She walked Sara into the other room. "Up here," Mrs. Glen called from a twisting flight of stairs. The front door banged shut just as Sara started up the steps. "Oh, I must have left the door open. The wind must have shut it." Mrs. Glen said. Again they started up the stairs.
They walked up the enormous stairway. Halfway up detective Sara noticed a weather vane through the window. She realized that the wind was blowing west and in order for it to have shut the door it would have to have been blowing east. Then Sara realized for the first time that there was a third set of footsteps on the stairs. Then it dawned on her and she realized she had walked into a trap. How did Sara know she had walked into a trap?
Hint:
Detective Sara Dunts realized she had walked into a trap when she heard the extra set of footsteps. Hearing the footsteps on the stairs made her remember what her partner had said, "Mr. John Gooding had mysteriously vanished from his one story home." She then realized that this was not Mr. Goodings home because at that very moment she realized that she was climbing stairs in a supposedly one story house. Sara immediately called for backup and arrested Mrs. Glen. She then walked down the stairs to find Mr. Gooding near the bottom. The two had planned on kidnapping and killing Sara for putting Mr. Goodings niece and Mrs. Glens son in jail for murder. Both went to jail to serve their time. Did you answer this riddle correctly?
YES NO
YES NO
Construction Site Murder Riddle
A workman was killed at a construction site. The police began questioning a number of the other fellow workers. Based on past scrapes with the law, many of the following workers were considered prime suspects:
* The electrician was suspected of wiretapping once but was never charged.
* The carpenter thought he was a stud. He tried to frame another man one time.
* The glazier went to great panes to conceal his past. He still claims that he didnt do anything, that he was framed.
* The painter had a brush with the law several years ago.
* The heating, ventilation and air conditioning contractor was known to pack heat. He was arrested once but duct the charges.
* The mason was a prime suspect because he gets stoned regularly.
* The cabinet maker is an accomplished counter fitter.
The autopsy led the police to arrest the carpenter, who subsequently confessed. Why?
* The electrician was suspected of wiretapping once but was never charged.
* The carpenter thought he was a stud. He tried to frame another man one time.
* The glazier went to great panes to conceal his past. He still claims that he didnt do anything, that he was framed.
* The painter had a brush with the law several years ago.
* The heating, ventilation and air conditioning contractor was known to pack heat. He was arrested once but duct the charges.
* The mason was a prime suspect because he gets stoned regularly.
* The cabinet maker is an accomplished counter fitter.
The autopsy led the police to arrest the carpenter, who subsequently confessed. Why?
Hint:
The evidence against him was irrefutable. It was found that the workman, when he died, was hammered. Did you answer this riddle correctly?
YES NO
YES NO
Pine Trees In Trouble Riddle
Hint:
Tide Pool Riddle
Hint:
Saturn Has Them Riddle
Saturn has them. Married people wear them. A tree's age can be determined by counting them. What is it?
Hint:
How Many Acorns Riddle
Hint:
Shotgun Pete Riddle
Shotgun Pete owned a lot of guns. He left a quarter of them in Death Valley, gave one to each of the three passengers in the stagecoach, and kept half of them with him. How many guns did Pete own?
Hint:
Finding Anna's Picture Riddle
Once upon a time there was a beautiful princess named Anna. Anna's father, the King, wanted to be sure his daughter married an intelligent man. To test his daughter's suitors the King hid Anna's picture in one of three boxes. The suitor had to be able to select the box with Anna's picture on one try and within twenty seconds. On the gold box was the message "Anna's picture is in this box". The silver box had the message "Anna's picture is not in this box." "Anna's picture is not in the gold box" was written on the bronze box. The King would tell each suitor "Only one of the three messages is correct." Which box contained Anna's picture?
Hint:
The silver box contained Anna's picture. If her picture had been in the gold box, two statements would have been true. (The messages on both the gold box and the silver box.) If her picture had been in the bronze box, two statements would have been true. (The messages on the bronze box and the silver box.) Did you answer this riddle correctly?
YES NO
YES NO
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