The speed of the river is 2.2 km / h. The boat’s own speed is 15.4 km / h. What route did the boat take upstream in 3.5 hours?

In order to find out which way the boat went against the current in 3.5 hours. First, it is necessary to calculate which way the boat goes against the current in 1 hour.

Let’s find the speed of the boat against the current, for this we need to subtract the speed of the current from the speed of the boat.

15.4 – 2.2 = 13.2 km / h.

Let’s find which way the boat went against the current in 3.5 hours, according to the formula:

S = V × t, where

S – the path that the boat traveled, km,

V – speed of the boat against the stream, km / h,

t is the time the boat was sailing, h.

S = 13.2 × 3.5 = 46.2 km.

Answer: The boat covered 46.2 km.