Question

A steamer goes downstream and covers the distance between two ports in 5 hours while it covers the same distance upstream in 6 hours. If the speed of the stream is 1 km/hr, find the speed of the steamer in still water.

Answer 1

Given, speed of stream = 1 km/h

Let speed of the steamer in still water be x km/h.

Then, speed of steamer downstream = (x + 1) km/h

And speed of steamer upstream = (x – 1) km/h

According to the question,

Distance covered upstream = Distance covered downstream

⇒ (Speed of steamer in upstream) × Time taken upstream

= (Speed of steamer downstream) × Time taken downstream  ...[∵ Distance = Speed × Time]

⇒ (x – 1) × 6 = (x + 1) × 5

⇒ 6x – 6 = 5x + 5

⇒ 6x – 5x = 6 + 5

∴  x = 11

Therefore, the speed of steamer in still water is 11 km/h.