Question

A boat covers a certain distance upstream in 10 hours and it covers the same distance downstream in 6 hours if the speed of stream is 4 kilometre per hour find the speed of boat in still water​

Answer 1

Answer:

10

Step-by-step explanation:

it is a ratio question ha that is 10×4and 6is÷ by 10

Answer 2

Step-by-step explanation:

Let the speed of the water in still water = x

Given that speed of the stream = 4 kmph

Speed downstream = (x+4) kmph

Speed upstream = (x-4) kmph

He travels a certain distance downstream in 6 hour and come back in 10 hour.

ie, distance travelled downstream in 6 hour = distance travelled upstream in 10 hour

since distance = speed × time, we have

(x+4)6=(x−4)10

=> (x + 4)3=(x - 4)5

=> 3x + 12 = 5x-20

=> 5x-3x=20-12

=> 2x=8

=> x=4

speed = 4 km/h

hope it helps you

with regards @Arsh