Use 72 cm wire to enclose a rectangle whose length to width ratio is 5:4. What is the area of the rectangle in square centimetres.
用72厘米铁丝围成长与宽的比是5：4的长方形．长方形的面积是多少平方厘米．
<gadget id="calculator">72 / 2</gadget>
<output>36</output>

<gadget id="calculator">4 + 5</gadget>
<output>9</output>

<gadget id="calculator">5 / 9</gadget>
<output>5/9 = around 0.555556</output>

<gadget id="calculator">36 * (5/9)</gadget>
<output>20</output>

<gadget id="calculator">5 + 4</gadget>
<output>9</output>

<gadget id="calculator">4 / 9</gadget>
<output>4/9 = around 0.444444</output>

<gadget id="calculator">36 * (4/9)</gadget>
<output>16</output>

<gadget id="calculator">20 * 16</gadget>
<output>320</output>

<result>320</result>