a container has 40 l milk . 4 l milk is taken out and replaced with water , the process done 3 times . what is the amount of milk now left ?	Choose the correct answer.
A) 29.16 l B) 29.19 l C) 29.12 l D) 29.11 l E) 29.14 l

Rationale: explanation : 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 = 40 l y = 4 l n = 3 ) and solving = > 40 - ( 1 - 4 / 40 ) 3 = 29.16 l answer : a
Answer: A