Problema Solution
A motorboat travels in hours going upstream and in hours going downstream. What is the rate of the boat in still water and what is the rate of the current?
Answer provided by our tutors
Let
x = upstream travelling time in hours with speed v1
y - downstream travelling time in hours with speed v1
If the distance passed is d then we can write down
v1 = d/x
v2 = d/y
Let 's' be the rate of the boat in still water and 'c' be the rate of the current then
s + c = v1
s - c = v2
s = (v1 + v2)/2 = (1/x + 1/y) / 2*d the rate of the boat in still water
c = (v1 - v2)/2 = (1/x - 1/y) / 2*d the rate of the current