Alvin paddled for 3 hours with a 4-Km/h current to reach a campsite. The return trip against the same current took 7 hours. find the speed of the boat in still water. The speed of the boat in still water was Km/h?

Alvin's average paddling 3km/h. The speed of the boat in still water was Km/h is given below

Step-by-step explanation:

Let the boat speed in still water be x km/hr.

We know the current is 3 km/h so:

4 (x+3) = 7 (x-3)

4x + 12 = 7x - 21

-3x = - 33

x = 11 km/h

Therefore the speed of the boat in still water is 11 km/h