Some exercise for Brain :)

Question:

Varun, Radha, Arun and Sudha wants to cross the bridge at night. They have only one torch light with them. Only two can cross the bridge at a time. They need torch light to cross the bridge. Each of them walks at a different speed. Varun needs 1 minute, Radha needs 2 minutes, Arun needs 5 minutes and Sudha needs 10 minutes.

A pair must walk together at the rate of the slower person.

How these people can cross the bridge within 17 minutes?

Solution:

First Varun and Radha walk across the bridge, it takes 2 minutes.

Varun walks back with the torch light, which takes 1 minute.

Then Arun and Sudha walk on the bridge, which takes 10 minutes.

Radha comes back with the torch light, it takes 2 minutes.

Finally Varun and Radha walks across the bridge, which takes 2 minutes.

Total = 2 + 1 + 10 + 2 + 2 = 17 minutes.

Regards

10on10 Team