What is the area in square meters of a square plank with side length (4/5) meters?
一块正方形木板边长(4/5)米，面积是多少平方米．
<gadget id="calculator">4 / 5</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">(4/5) * (4/5)</gadget>
<output>16/25 = around 0.64</output>

<result>16/25 = around 0.64</result>