The Company has $ 1 m debenture stock in issue quoted at $50 per $100 of nominal stock,$625 000 preference shares of $1 each quoted at 40 cents ; and 5 m ordinary shares standing at 25 cents. The cost of Capital of these securities is 9% , 12 % , and 18 % respectively. This capital structure is to be maintained. What is the combined cost of Capital ?