If a rectangle is 6 cm long and 4 cm wide, what is the area of the square equal to its perimeter?
一个长方形长6厘米，宽4厘米，与它周长相等的正方形的面积是多少平方厘米．
<gadget id="calculator">6 + 4</gadget>
<output>10</output>

<gadget id="calculator">2 / 4</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">10 * (1/2)</gadget>
<output>5</output>

<gadget id="calculator">5 * 5</gadget>
<output>25</output>

<result>25</result>