Uncle Chen used a 60cm lead alloy strip to make a rectangular mirror frame with a length of 18cm. Could you help Uncle Chen figure out how big a mirror should be?
陈伯伯用一根60厘米的铅合金条做了一长18厘米的长方形镜框，请你帮陈伯伯算一算，应配一块多大面积的镜子？
<gadget id="calculator">60 / 2</gadget>
<output>30</output>

<gadget id="calculator">30 - 18</gadget>
<output>12</output>

<gadget id="calculator">18 * 12</gadget>
<output>216</output>

<result>216</result>