IBPS Clerk Prelims Model Paper 20

Suppose the speed of boat in still water is ‘x’ km/hr & that of stream is ‘y’ km/hr.
Then,
ATQ
(x+y)/y = 9/1
9y = x + y
x = 8y
y = 3 km/hr
So, x = 24 km/hr
Upstream speed = 24 – 3 = 21 km/hr Hence, distance travelled upstream in 5 hours = 21 × 5 = 105 km