The speed of the boat along the river is 22 km h. And against the current 18 km h.

The speed of the boat along the river is 22 km h. And against the current 18 km h. Find the speed of the current and the proper speed of the boat.

Speed ​​of the boat along the river (V along the current) = 22 km / h;
The speed of the boat against the river flow (Vpr. Flow) = 18 km / h;
River flow speed (Vcurrent) -? km / h;
Boat speed (Vk.) -? km / h;
Speed ​​of the boat along the river:
Vin flow = Vk. + Vcur. = 22 km / h, hence Vk. = Vin flow. – V leak. = 22 – Vcur. (one);
Speed ​​of the boat upstream of the river:
Vpr. tech. = Vk. – V leak. = 18 km / h, hence Vk. = Vpr. tech. + Vcur. = 18 + Vcur. (2);
Substitute the resulting expression (1) into expression (2):
22 – V leak. = 18 + Vflow, we solve the resulting equation:
4 = 2V leak;
V leak. = 2 km / h,
We substitute the obtained value of the river flow speed into the expression for finding the speed of the boat:
Vк. = 22 – Vcur. = 22 – 2 = 20 km / h.
Answer: The speed of the river is 2 km / h, the own speed of the boat is 20 km / h.