An industrial solvent of 90% strength is prepared and stored Q in a 150 litres capacity container. The container is filled to 80% of its capacity. It is required to decrease the concentration of the solvent in the container to less than 60°%. For doing this, eithe pure water can be added to it and/or solution can be removed. But removal can only be done if there is no place for adding water. At a given time, only 10 litres of the solution can be added or removed. How many times should water be added to the solution?

Options

A. 4
B. 5
C. 9
D. 6

Answer

D