A motorboat travels a certain distance in still water in 5 hours. A raft floats down a river and travels the same distance as the motorboat
in 20 hours.
How long will it take the motorboat to travel the distance in question
by traveling downstream?
How long will it take the motorboat to cover that distance traveling
upstream?
27
A jet ski left port B for port A at the same time a raft left port A for port
B. The jet ski and the raft met 4 hours after departure, and the jet ski
reached port A20 minutes after that. How long does it take the raft
to travel the distance between ports A and B?
29
It takes a motorboat twice as much time to cover a certain distance when
going upstream as when going downstream. Write the ratio of the speed
of the motorboat in still water to the speed of the current.