The base of a parallelogram is 10 decimeters and the height is half the length of the base. If the area of a triangle is equal to the area of the parallelogram, what is the area of the triangle in square decimeters?
一个平行四边形的底是10分米，高是底长度的一半．一个三角形与这个平行四边形的面积相等，这个三角形的面积是多少平方分米．
<gadget id="calculator">10 / 2</gadget>
<output>5</output>

<gadget id="calculator">10 * 5</gadget>
<output>50</output>

<result>50</result>