Question

a man rows 30km downstream in 7 hours 30 minutes and 10 km up stream in 5 hours. find the speed of the boat in still water and also the speed of current.​

Answer 1

Answer:

Let man's rowing speed be "x" and the current speed be "y".

When rowing downstream, the current speed adds to the man's rowing speed. When rowing upstream, the current speed acts against the man's rowing speed.

distance=speed×time

so while moving downstream,

30=[x+y] × 5. (eqn-1)

while moving upstream

18=[x-y] × 5. (eqn-2)

adding eqn 1 &2 we get

48= 10x

so x= 4.8

putting this value of x in eithr eqn 1 or 2, we get the current's speed. y= 1.2 Km/hr.

Step-by-step explanation:

Hope this helps mate ☺️.