Question

a streamer goes downstream from one point to another in 9 hours it covers the same distance upstream in 10 hours its speed of stream will be 1 km per hour find the speed of stream hour in still water and distance between ports​

Answer 1

Answer:

Let the speed of the steamer in still water is x km/h and distance is d.

Then, speed of steamer downstream (u)= speed of steamer in still water+speed of stream=x+1

Speed of steamer upstream (v)=speed of steamer in still water-speed of stream=x−1

Distance covered by steamer upstream (d)=10(x−1) ......(1)

Distance covered by steamer downstream (d)=9(x+1) ......(2)

From equation (1) and (2),

10(x−1)=9(x+1)

10x−10=9x+9

10x−9x=9+10

x=19 km/h

Substituting this value in equation(1),

Distance(d)=10(19−1)=180km

Hence, the speed of the steamer in still water is 19km/h and the distance between the ports is 180km.

Answer 2

Answer:

Distance = 180km and speed in still water is 19km/hr

Step-by-step explanation:

Time taken downstream = 9hrs

Time taken upstream = 10h

Let the distance be d

Let v be the speed downstream and u be the speed upstream.

Speed of stream = 1km/hr

Speed of stream = v-u/2

v-u = 2km/hr

v = d/9

u = d/10

d/9 - d/10 = 2

10d-9d/90 = 2

d/90 = 2

d = 180 km

v = 20km/hr

u = 18km/hr

Speed of boat in still water = v+u/2 = 20+18/2 = 38/2 = 19km/hr