Beauty of Mathematics and Mathematical expertise

NICE

Now another question:

There are 5 people who need to cross a rickety bridge in 30 minutes. Because of its dilapidated condition, the bridge can only support up to 2 people at any given time. In addition, since it is pitch black out and there is only one lantern between the 5 people, anybody crossing the bridge must carry the lantern (or if two people are crossing the bridge at the same time, then one of them must be carrying the lantern). Someone must always bring the lantern back to the people who haven't crossed the bridge yet, so that when they cross, they don't fall through the holes in the bridge. You must take into account the additional time it will take for them to cross back.

The 5 people can cross the bridge at the rate of 1, 3, 6, 8 and 12 minutes, each way.

There are no tricks: you can't carry anyone, or throw the lantern or drop it on the bridge, or swim across.

source: this question has been copied from a website, but figures has been changed.

Dear ashu ,

plz check ur question , i think there is some mistake

as per ur question , the minimum time taken to cross the bridge would be 32 mins

there is no mistake in the question, bridge can be crossed even 29 minute....

but how,

i will tell

but let others to try.....