AFCAT Model Paper 8

Downstream speed of the boat = 12 km/hr
Upstream speed of the boat = 6 km/hr
Formula Used:
Speed of boat in still water = Speed of (Upstream + Downstream)/2
Calculation:
According to the question
Speed of the boat in still water =

(12+6)

2

⇒ 9 km/hr
Now, we have to find the time taken by the boat to cross 27 km in still water,
⇒Time =

27

9

⇒ 3 hours
∴ The required time is 3 hours.