The ratio of width to length of a rectangle is 2:5, and the ratio of width to length is 12 decimeters. What is the area of the rectangle in square decimeters?
长方形的宽和长的比是2：5，宽比长短12分米，长方形的面积是多少平方分米．
<gadget id="calculator">5 - 2</gadget>
<output>3</output>

<gadget id="calculator">12 / 3</gadget>
<output>4</output>

<gadget id="calculator">4 * 5</gadget>
<output>20</output>

<gadget id="calculator">4 * 2</gadget>
<output>8</output>

<gadget id="calculator">20 * 8</gadget>
<output>160</output>

<result>160</result>