The motor boat’s own speed in still water is 11.4 km, its speed along the river is 12.27 km / h.

The motor boat’s own speed in still water is 11.4 km, its speed along the river is 12.27 km / h. Find the speed of the boat upstream.

Let’s find how much faster the boat goes with the current, i.e. river speed:

1) 12.27 – 11.4 = 0.87 (km / h).

Thus, the speed of the boat will decrease by this speed if it goes against the current:

2) 11.4 – 0.87 = 10.53 (km / h).

Answer: The speed of the motor boat when driving against the current is 10.53 km / h.