Lucille is painting her room. Two of her walls are 3 meters wide and 2 meters tall. The third wall is 5 meters wide and 2 meters tall. The final wall is 4 meters wide and 2 meters tall. If each can of paint covers 2 square meters, how many cans of paint does Lucille need?
Please reason step by step, and put your final answer within \boxed{}.
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