A man can swim along the stream at 3 km/h and against the stream at 2 km/hr. How long will he take to swim 7 km in still water?
Answer & explanation
Correct answer: option 2
Let Man's Velocity in Still water be "v"
Let Velocity of Stream be "s"
Man's Upstream Velocity = 2 = v-s
Man's Downstream Velocity = 3 = v+s
⇒2v = 5
v = 2.5
For 7 km, time taken = 7/2.5 = 2.8 = 2 hours and 48 minutes
The correct answer is Option (2) → 2 h 48 m