Question

the connecticut river flows at a rate of 4 km/hr for the length of a popular science route. in order for a cruiser to travel 60 km upriver anf then return in a total of 8 hr. , how fast must the boat be able to travel in still water?

Answer 1

if the boat travels 60 km in 8 hours, the rate it travels upstream is then 60/8 km/hr, or 15/2 km/hr. if the river is traveling against it at 4 km/hr, it subtracts from the boats max speed by 4 km/hr, and 15/2 + 4 or 23/2 km/hr is then the boats speed in still water.