narrow bridge crossing It takes Bob 1 minute to cross a dark bridge; Eleanor 2 minutes; Anthony 5 minutes; Lori 10 minutes. What is the shortest amount of time that all four people need to cross this narrow bridge ~ if only 1 or 2 can cross at a time; sharing the same flashlight to see where they're walking? When 2 cross together, they must walk at the speed of the slower person. Congratulations to these solvers as of BEST TIME by Niven Brown, Albert Frank, Aaron Glasenapp Napawong Leelaprechalert and Luc Vingerghoets. FOLLOWED by Valmai Osborn, Matthew Hutchins, Jay Willner, Frank Womack, Christian Stahl and Gav Fyfe. |
