Question

a stream goes downstream from one station to another in 9 hours. it covers the same distance upstream in 10 hours. if the speed of the stream is 1 km/hr.find the speed of the streamer

Answer 1

Hey

Here is your answer,

Given, speed of the stream = 1 km/hr

Let the speed of steamer in still water be xkm/hr.

Speed of the steamer downstream = Speed of steamer in still water + Speed of the stream = (x + 1) km/hr

Speed of the steamer upstream = Speed of steamer in still water – Speed of the stream = (x – 1) km/hr

Distance covered by the steamer downstream in 9 hours = 9 (x + 1) km
Distance = Speed × Time)
Distance covered by the steamer upstream in 10 hours = 10 (x – 1) km.
Distance covered by steamer downstream in 9 hours = Distance covered by steamer upstream in 10 hours

∴ 9 (x + 1) = 10 (x – 1)
⇒ 9x + 9 = 10x – 10
⇒ 9x – 10 = – 10 – 9
⇒ – x = – 19
⇒ x = 19
∴ Speed of steamer in still water is 19 km/hr.

Distance between the two ports = 9 (x + 1) km = 9 (19 +1) km = 9 × 20 km = 180 km

Hope it helps you!