Question

a Boat goes 24 km upstream and 28 km downstream in 6 hours it goes 30 km upstream and 21 km downstream in 6 1 over 2 hours find the speed of a boat in still water and also the speed of the stream​

Answer 1

Answer:

Let, speed of boat in still water be 'x' & speed of stream be 'y'.

speed while upstream = (x-y)

speed while downstream =(x+y)

Accordingly,

    24/(x-y)  +  28/(x+y)  =  6 ...(i)

    30/(x-y)  +  21/(x+y)  =  6 1/2 (6 and a half) ...(ii)

Now, solving equations (i) and (ii) we get,

  x = 10  y = 4

Ans- The speed of boat in still water is 10 km/hr, and speed of the stream is 4 km/hr.

Step-by-step explanation:

Note: Distance is always constant whatever the speed and time may be.

Answer 2

Answer:

let the speed of boat in water =x

speed of stream =y

up stream = (x-y)

down steam =(x+y)

Step-by-step explanation:

24(x-y) + 28(x+ y) =6 ---------(1)

30(x-y) +21(x+y) =6×1/2-------(2)

on solving,

we get,

x=10, y=4

speed of boat in water =10

speed of stream =4

hope it helps