Answer:
At t=0, Volume of Water =
= 3,000 Litre
After t hours , the Volume of water in the tank = 
As it is also given , At the end of every hour there is a x% less water in the tank then at the start of the hour
= Amount of water after an hour = 3,000 -
= 3,000 - 30 x
= Amount of water after two hour =(3,000 - 30 x) - (3,000 - 30 x)×
= (3,000 - 30 x)
Also, 
⇒
= 288120
⇒300000 - 3000 x - 3000 x + 30 x² = 288120
⇒ 30 x ² - 6,000 x + 11880= 0
Dividing both sides by 30, we get
⇒ x² - 200 x + 396=0
Factorizing the quadratic expression
(x -198)(x-2) = 0
x = 198, x = 2
⇒ Which gives a value of x = 2 as a possible solution of this equation.
Also, 
k = 

k =
= 0. 999.......(non terminating repeating)
k= 0.999 (approx)