Steps to Cross in 17 Minutes:
- A & B cross first (2 minutes) → A carries the flashlight.
- Now A & B are on the far side.
- A returns with the flashlight (1 minute) → Now only A is on the starting side.
- C & D cross together (10 minutes) → B holds the flashlight.
- Now C & D are on the far side with B.
- B returns with the flashlight (2 minutes) → Now only B is on the starting side.
- A & B cross again (2 minutes) → Now everyone is on the far side.
Total Time:
2 + 1 + 10 + 2 + 2 = 17 minutes