In what ratio must water be mixed with milk so as to make a

In what ratio must water be mixed with milk so as to make a profit of 16*(2/3)% on selling the mixture at a rate same as that of cost price of milk.Given that milk man mixes bottled water instead of tap water and the cost of Bottled water is 20% of the cost of milk

A. 7:41
B. 1:6
C. 6:7
D. 5:23
E. 1:7