A basketball court is 18 meters wide and 12 meters longer than it is wide. What is the area of this basketball court?
一个篮球场，宽18米，长比宽多12米．这个篮球场的面积是多少？
<gadget id="calculator">18 + 12</gadget>
<output>30</output>

<gadget id="calculator">30 * 18</gadget>
<output>540</output>

<result>540</result>