SSC CPO 2024 PYQ — Question 123

The correct answer is option 1 i.e. 6.22.

Given that, Speed of current = 3 km/h

Downstream speed = speed of boat in still water + speed of current

According to the given question,

Downstream speed = $16.9 \over {52 \over 60}$

⇒ speed of boat in still water + speed of current = 19.5 km/h

⇒ speed of boat in still water + 3 = 19.5

⇒ speed of boat in still water = 16.5 km/h

Let the time taken by boat to cover 84 km upstream be t hours.

Upstream speed = speed of boat in still water - speed of current

⇒ $84 \over t$ = 16.5 - 3

⇒ t = $84 \over 13.5$

⇒ t = 6.22 

Hence the time (in hours) will the boat take to travel 84 km upstream is 6.22.