Problema Solution
A Paddle boat can move at a speed of 4km/h in still water. The boat is paddled 20km down stream in a river in the same time it takes to go 10km upstream. What is the speed of the river?
The speed of the river is _____km/h.
Answer provided by our tutors
let x be the speed of river
then , x + 4 = 20 / t and 4 - x = 10 / t
4 + x / 4- x = 2
4+x = 8 - 2x
3x = 4
x = 4/3