Two sticks 5 decimeters long and two sticks 4 decimeters long are used to form a rectangle. What is the perimeter of this rectangle?
用两根长5分米和两根长4分米的木棒摆成一个长方形，这个长方形的周长是多少分米．
<gadget id="calculator">5 + 5 + 4 + 4</gadget>
<output>18</output>

<result>18</result>