There are A,B,C,D at one end of the bridge.they have to cross within 17 minutes.only 2 can cross the bridge at atime .since it is very dark one has to come back to show the light and its said that A can cross the bridge in 1 min ,B can cross at 3min ,C in 5 min and D in 10 min.How and at What time will they cross the bridge
6 years later a no one answer her, dang
To find the solution, we need to come up with a strategy that ensures the four individuals cross the bridge within 17 minutes. Here's how we can do it:
1. A and B cross the bridge together, which takes 3 minutes. The time is now at 3 minutes, and A is on the other side with the flashlight.
2. A goes back to the starting side with the flashlight, which takes an additional 1 minute. The time is now at 4 minutes.
3. C and D cross the bridge together, which takes 10 minutes. The time is now at 14 minutes, and B is on the other side with the flashlight.
4. B goes back to the starting side with the flashlight, which takes an additional 3 minutes. The time is now at 17 minutes.
5. Finally, A and B cross the bridge together, which takes 3 minutes. The total time is now at 20 minutes.
Therefore, the four individuals will cross the bridge within 17 minutes at the time of 20 minutes.