But what would happen to the cost of Big Macs if McDonald's actually paid workers $15 an hour?A Big Mac would cost just 68 cents more, while every item on the Dollar Menu would require an additional 17 cents, the study found. That includes a doubling of the salary of all McDonald's employees, from workers earning the base wage of $7.25 per hour to chief executive Donald Thompson, who was paid $8.75 million last year. Currently, only 17 cents of every dollar McDonald's earns goes to paying wages and benefits for its 500,000 U.S. employees, according to  research Arnobio Morelix ofUniversity of Kansas. MSN Money