Each of the four persons can cross the bridge at a different time, namely 3, 7, 13, and 17 minutes, respectively. Only two people can cross at a time. What is the minimum time in which all four can cross the bridge?
Each of the four persons can cross the bridge at a different time, namely 3, 7, 13, and 17 minutes, respectively. Only two people can cross at a time. What is the minimum time in which all four can cross the bridge?
Explanation
both 3 and 13 reach their destination at the same time after 3 minutes
hence the time taken is 7+10+3=20 minutes.