top button
Flag Notify
    Connect to us
      Site Registration

Site Registration

What order should they cross to get everyone across and get to the concert?

0 votes
228 views

Four members of a band are walking to a night concert.
They decided to take a short-cut, but must cross a bridge.
Luckily they have one flashlight. Because of the varying size of their instruments, it takes each member a different amount of time to cross the bridge - it takes the first person one minute, the second person two minutes, the third person five minutes and the fourth person ten minutes.
They must cross the bridge in pairs, travelling at the slower speed so if the one minute person went with the ten minute person, it would take a total of ten minutes. Since there is only one flashlight, one person must come back across the bridge, then another pair can cross.
They only have 17 minutes to cross the bridge and still get to the concert on time.
What order should they cross to get everyone across and get to the concert?

posted Aug 21, 2018 by Aastha Joshi

Share this puzzle
Facebook Share Button Twitter Share Button LinkedIn Share Button

1 Answer

0 votes
  1. The 1 min person & the 2 min person cross the bridge- total of 2 minutes,
  2. The 1 min person comes back with flashlight - total of 3 minutes,
  3. The 5 min person & the 10 min person cross the bridge- total 13 minutes,
  4. The 2 min person goes back- total of 15 minutes,
  5. The 1 min person & 2 min person cross together- total of 17 minutes
answer Aug 21, 2018 by Hanifa Mammadov



Similar Puzzles
0 votes

There are four people in an adventure race that need to get across a lake. They have a small canoe. The rules say that only the slowest person in the canoe can paddle, only one or two can be in the canoe at a time, and they must all cross in the canoe. From practice, they know that: Arnav can paddle across in 1 minute. Bilal can paddle across in 2 minutes. Suresh can paddle across in 5 minutes. Mohan can paddle across in 10 minutes.
How do they get everyone across the river in the fastest time without breaking the rules?

0 votes

Seven men and two boys need to cross a river. The one canoe is tiny and can carry either one man or two boys. How many times does the boat have to cross the river for everyone to get to the other side?

0 votes

There is a river to cross using a river raft and there are eight people (father, mother, policeman, thief, 2 daughters and 2 sons). No one knows to operate the raft except the adults and also excluding the thief. Only two people can go in the raft at a time. The raft should keep coming back and forth in order to pick and drop the people.
Rules to be followed:
Father: the father cannot stay in the raft or outside the raft without the presence of the mother.
Mother: the mother cannot stay in the raft or outside the rat without the presence of the father.
Thief: the thief is not allowed to stay with any of the family members unless there is a policeman.
Policeman: the policeman can travel with anyone.
2 sons and 2 daughters: they are not allowed to travel in the raft without the presence of an adult. They cannot either travel in the presence of only thieves without the policeman. The sons cannot be with their mothers without their father’s supervision. The daughters are not allowed to be there with their fathers without the supervision of their mothers. But the daughters and the sons can be left unsupervised (as long as the other rules are applied).
What is the sequence that the people should follow in order to cross the river through the raft keeping in mind all the rules?
The rules are applicable not only in the raft but also outside the raft.

0 votes

Cross out 6 letters and you'll find a word hidden there. This word should be spelled out in the same order as is written here:
SBAIXNLETATNERSAS

0 votes

A man has a medical condition that requires him to take two kinds of pills, call them A and B. The man must take exactly one A pill and exactly one B pill each day, or he will die. The pills are taken by first dissolving them in water.

The man has a jar of A pills and a jar of B pills. One day, as he is about to take his pills, he takes out one A pill from the A jar and puts it in a glass of water. Then he accidentally takes out two B pills from the B jar and puts them in the water. Now, he is in the situation of having a glass of water with three dissolved pills, one A pill and two B pills. Unfortunately, the pills are very expensive, so the thought of throwing out the water with the 3 pills and starting over is out of the question. How should the man proceed in order to get the right quantity of A and B while not wasting any pills?

...