AFCAT Model Paper 5

Given:
Speed of boat in still water = 12 km/h
Speed of current = 3 km/h
Distance covered in downstream as well as in upstream = 135 km
Calculation:
Speed of boat upstream = (12 - 3) = 9 kmph
Speed of boat downstream = (12 + 3) = 15 kmph
Time taken = (Distance travelled)/Speed
Total time taken for entire journey =

135

15

+

135

9

⇒ (9 + 15) hours
⇒ 24 hours
∴ Time taken to cover the entire journey is 24 hours.