The cost of a double cheeseburger is approximately **4.4 yuan**.

According to public information, the raw materials of double cheeseburger are high-gluten flour, eggs, milk, sugar, high-sugar resistant yeast, salt, sesame, butter or corn oil. The cost of making a double-decker cheeseburger is about 2 yuan. Including the loss of electrical appliances and other resources, the cost of a McDonald's double-decker cheeseburger is about 4.4 yuan.