A rectangular swimming pool is 45 meters long and 15 meters wide. What is the perimeter of the swimming pool?
一个长方形游泳池长45米，宽15米，这个游泳池的周长是多少米？
<gadget id="calculator">45 + 15</gadget>
<output>60</output>

<gadget id="calculator">60 * 2</gadget>
<output>120</output>

<result>120</result>