Question 898374
distance = 8

let speed of boat be x
speed of current be y

down stream speed = x+y
upstream speed = x-y

time down stream = 2
time upstream = 4

t=d/r

8/(x+y )= 2
x-y=4...............(1)

8/(x-y)= 4
x-y =2..............(2)

solve (1) & (2)

2x=6
x=3
y=1