If the length of a rectangle is 10 decimeters and the width is 4 decimeters less than the length, what is the area of the rectangle in square decimeters?
一个长方形的长是10分米，宽比长少4分米，这个长方形的面积是多少平方分米．
<gadget id="calculator">10 - 4</gadget>
<output>6</output>

<gadget id="calculator">10 * 6</gadget>
<output>60</output>

<result>60</result>