Question

A boat goes 16 km upstream and 24 km downstream in 6 hour . also it cover 12 km upstream 36km downstream in the same time . find the speed of the the boat in still water and that of the stream .
plz bro answer immedetly. ​

Answer 1

Step-by-step explanation:

Let speed of the boat in still water =x km/hr, and

Speed of the current =y km/hr

Downstream speed =(x+y) km/hr

Upstream speed =(x−y) km/hr

$t = \frac{d}{s} \:$

24/x+y +16/x-y. [1]

36/x+y +12/x-y. [2]

$\frac{1}{x + y} = u$

$\frac{1}{x - y} = v$

r

equation becomes,

24u+16v=6

Or, 12u+8v=3 ... (3)

36u+12v=6

Or, 6u+2v=1 ... (4)

Multiplying (4) by 4, we get,

24u+8v=4v … (5)

Subtracting (3) by (5), we get,

12u=1

$u = \frac{1}{12}$

Putting the value of u in (4), we get, v= 1/4

$\frac{1}{x + y} = \frac{1}{12}$

$\frac{1}{x - y} = \frac{1}{4}$

Thus, speed of the boat upstream =4 km/hr

Speed of the boat downstream =12 km/hr