The area of a parallelogram is 20 square decimeters, if the base and height are reduced by 2 times, what is its area?
一个平行四边形的面积是20平方分米，如果底和高都缩小2倍，则它的面积是多少．
<gadget id="calculator">2 * 2</gadget>
<output>4</output>

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

<result>5</result>