It's not so much the cost of extraction that's involved in setting the price, it's the price needed for the producers to balance their budgets. Money needs to be spent on the population to prevent another Arab spring. Health services, education and secure government jobs need to be provided to buy off the general public.
Imports need to be paid for and bills met. Most producers have spending which requires an oil price in the $80 - $100 a barrel range to balance the books.