A container has 40L milk. 4L milk is taken out and replaced with water, the process done three times. What is the amount of milk now left?
Answer: C
In regard to the problem let after n times liquid in the container is x and liquid removed is y
=>Liquid in container= x
=>Liquid removed= y
After one trial, quantity of pure liquid= x- (1-y/x)
After n trials quantity of pure liquid = x - (1 -y/x)n
Therefore, Putting the values ( x = 40L y = 4L N=3) and solving
=> 40- (1-4/40)3
= 29.16L