HELP PLEASE I GIVE 30 POINTS boat Speed is equal in still water 19 kmch. Ivan on a current floated 11 km and spent on it so much time how many went against the stream 8 km. Calculate watercourse speed.

318
S = v * t - a formula of a way-------------------------------------Let x (km/h) - watercourse speed, then 19 + x (km/h) - boat speed on a watercourse; 19 - x (km/h) - boat speed against the current the rivers. Equation: 11: (19 + x) = 8: (19 - x) - it is a proportion 8 * (19 + x) = 11 * (19 - x) - property of a proportion 152 + the 8th = 209 - the 11th the 8th + the 11th = 209 - 152 of the 19th = 57 x = 57: 19 x = 3 Answer: 3 km/h - watercourse speed.
235
Answer add