I was working my way through some Puzzles in Discrete Maths by Rosen, when I came across the following question:
- A Pokemon Hunter is rowing upstream a brook
- As he passes under the 'bridge-of-curse', he throws a Pikachu into the brook
- 5 minutes later, he realises that Pikachu will die and he should not have done that
He rows back and picks Pikachu 3km. downstream of the 'bridge-of-curse'
What is the speed of the river flow?
- Distance : 3km
- Time : 5 minutes + 5 minutes ( due to the stream's frame of reference ) = 10 minutes
- Speed = 3000 / 600 m/s = 5 m/s
Am I correct ? Seems a bit too easy ...