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### Brain Twister River Riddle

Brain Twister River Riddle - 31 July

A bridge is about to collapse. There are four people P, Q, R and S on one of the side. Before the bridge collapses, they want to cross it. Now since the bridge is too weak, it can only stand the weight of two people at a time. Also, it is night time and nothing is visible. They have just one torch with them.

Now P takes one minute to cross the bridge, Q takes two minutes to cross, R takes five minutes to cross and S takes ten minutes to cross.

The bridge will collapse in seventeen minutes. How will they be able to cross the bridge before it collapses?

1. P+Q cross (Running total = 2mins)
P returns (3)
R+S cross (13)
Q returns (15)
P+Q cross (17)

2. P+Q cross (Running total = 2mins)
P returns (3)
R+S cross (13)
Q returns (15)
P+Q cross (17)

3. Don Elcid EspeletaJuly 31, 2014 at 9:12 PM

P+Q cross (Running total = 2mins)
P returns (3)
R+S cross (13)
Q returns (15)
P+Q cross (17)

4. P carries R (1 min)
Q carries S (3 min)