How do I figure a Portfolio Return?

How do I figure a Portfolio Return?

At the beginning of the month, you owned $5,500 of Goodyear, $7,500 of Dunkin Donuts, and $8,000 of Reebok. The monthly returns for Goodyear, Dunkin Donuts, and Reebok were 7.44 percent, −1.36 percent, and −0.54 percent. What is your portfolio return?