A triangular board with a base of 12 decimeters and a height half the length of the base, what is the area of the board?
一块三角形木板，底是12分米，高长是底长的一半，这块木板的面积是多少？
<gadget id="calculator">12 / 2</gadget>
<output>6</output>

<gadget id="calculator">6 / 2</gadget>
<output>3</output>

<gadget id="calculator">12 * 3</gadget>
<output>36</output>

<result>36</result>