Jim, Jeanne, Louis and Anne 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. Jim needs 1 minute, Jeanne needs 2 minutes, Louis needs 5 minutes and Anne needs 10 minutes.
A pair must walk together at the rate of the slower person.
How much time will be required by  these people to  cross the bridge....and explain how?

Solution of "Todays puzzle 21-10-2011"

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