A rectangular plank is 24 cm long, if its length is cut off (1/5), the plank becomes a square. What is the area of this rectangular board?
一块长方形木板，长24厘米，如果把它的长锯掉(1/5)，这块木板就变成了正方形．这个长方形木板的面积是多少？
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 - (1/5)</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">24 * (4/5)</gadget>
<output>96/5 = around 19.2</output>

<gadget id="calculator">24 * (96/5)</gadget>
<output>2_304/5 = around 460.8</output>

<result>2_304/5 = around 460.8</result>