Carnival vista is a cruise ship. It can travel 125 km along the stream in 1 hours 15 minutes. If speed of the ship in still water is 75 km/h, then find the time taken by the ship to cover the same distance against the stream.
1). 5/4 hours
2). 5/2 hours
3). 5/3 hours
4). 5 hours
Let, speed of stream be x km/h.
∴ Speed of the ship along the stream = (75 + x) km/h
∴ Speed of the ship against the stream = (75 – x) km/h
According to question,
⇒ 1.25 × (75 + x) = 125
⇒ 93.75 + 1.25x = 125
⇒ 1.25x = 32.75
⇒ x = 25
∴ Speed of stream = 25 km/h.
∴ Speed of the ship against the stream = 75 – 25 = 50 km/h
∴ Required time = 125/50 hours = 5/2 hours