The motor ship takes 3 hours downstream and 2 hours against the current for 240 km.

The motor ship takes 3 hours downstream and 2 hours against the current for 240 km. The same motor ship in 3 hours upstream passes 35 km more than 2 hours downstream. Find the speed of the ship upstream and its speed downstream.

Let the speed of the ship along the current x km / h, and against the current at km / h. Let’s compose the equations:
3 * x + 2 * y = 240; y = (240-3 * x) / 2;
3 * y = 35 + 2 * x;
Substitute the value for y in the second equation:
3 * (240-3 * x) / 2 = 35 + 2 * x;
720-9 * x-70-4 * x = 0;
13 * x = 650; x = 50;
y = (240-150) / 2 = 45;
Answer: the speed of the ship is 50 km / h downstream and 45 km / h upstream.