Question

4 грибника заблудились в лесу и вечером вышли к реке, через реку подвесной мостик. На другой стороне – железнодорожная станция. Электричка уедет через 18 минут! 1 грибник может перейти мост за 1 минуту, второй — за 2, третий — за 5, а четвёртый – самый старый — за 10 минут. У них есть только один фонарик. Мост выдерживает только двоих. Если переходят двое, то они идут с меньшей из двоих скоростей. Двигаться по мосту без фонарика нельзя. Светить издалека нельзя. Носить друг друга на руках нельзя. Успеют ли грибники к электричке?

Answer 1

1+10 пошли туда
1 вернулся обратно с фонариком
1+5 пошли туда
1 вернулся с фонариком
1+2 пошли туда
Итого:22
значит не успеют

Answer 2

Что за задача  идиотская не очем задача у тебя училка тупая

Answer 3

The Problem

Four mushroom pickers are lost in the forest and in the evening they reach a river with a suspension bridge. On the other side of the river is a train station. The train will leave in 18 minutes. The first mushroom picker can cross the bridge in 1 minute, the second in 2 minutes, the third in 5 minutes, and the fourth, who is the oldest, can cross the bridge in 10 minutes. They only have one flashlight, and the bridge can only hold two people at a time. If two people cross the bridge together, they must walk at the slower person's pace. They cannot cross the bridge without the flashlight, shine the flashlight from a distance, or carry each other. The question is: will the mushroom pickers make it to the train on time?

Solution

To solve this problem, we need to find the optimal strategy for the mushroom pickers to cross the bridge in the shortest amount of time. Since the bridge can only hold two people at a time, the mushroom pickers will need to take turns crossing the bridge.

Let's analyze the possible scenarios:

1. The first and second mushroom pickers cross the bridge together. It will take them 2 minutes. 2. The first mushroom picker returns with the flashlight, which will take an additional 1 minute. 3. The third and fourth mushroom pickers cross the bridge together. It will take them 10 minutes. 4. The second mushroom picker returns with the flashlight, which will take an additional 2 minutes. 5. The first and second mushroom pickers cross the bridge together again. It will take them 2 minutes.

In total, this strategy will take 17 minutes for all four mushroom pickers to cross the bridge and reach the train station. Since the train will leave in 18 minutes, they will make it on time.

Conclusion

The four mushroom pickers will be able to reach the train station on time if they follow the strategy described above. They will need a total of 17 minutes to cross the bridge, which is within the 18-minute timeframe before the train departs.