Question

a steamer covers a certain distance upstream in a river in five and a half hour. It covers the same distance downstream in five hours. find the speed of the steamerin still water, When the speed of the stream is 1.5km/hr.

Answer 1

v = speed of boat in still water = ?

w = speed of water = 1.5 km/hr

t1 = time to travel downstream = 5 hrs

t2 = time to travel upstream = 5.5 hrs

d = one-way distance, which is the same upstream and downstream

 

Downstream:

 

d = (v + w)t1

 

Upstream:

 

d = (v - w)t2

 

(v + w)t1 = (v - w)t2

 

(v + 1.5)(5) = (v - 1.5)(5.5)

 

5v + 7.5 = 5.5v - 8.25

 

0.5v = 15.75

 

v = 31.5 km/hr

Hope This Helps :)