Question

a boat goes 16km upstream anf 24km downstream in 6 hours it covers 12 km upstream and 36km downstream in same time find the speed of boat in still water and that of stream

Answer 1

Answer

Simple:

let x be speed in still water and y be speed of stream

speed in upstream = x -y

speed in downstream = x+y

time = distance / speed

time = 6

16/x-y + 24/x+y = 6 ... (i)

12/x-y + 36/x+y = 6 ... (ii)

On solving the eq. we get,

72y = 6

y= 1/12 , substitute in equation (3), we get x = 1/4

Hence u – v = 4, u + v = 12

u = 8km/hr and v= 4km/hr