If the base of a triangle is 3 decimeters and the height is 1.8 decimeters, what is the area in square decimeters?
一个三角形形的底是3分米，高是1.8分米，面积是多少平方分米．
<gadget id="calculator">1.8 / 2</gadget>
<output>0.9</output>

<gadget id="calculator">3 * 0.9</gadget>
<output>2.7</output>

<result>2.7</result>