If the base of a triangle is 30 cm and the height is 1.2 decimeters, what is the area in square decimeters?
一个三角形的底是30厘米，高为1.2分米，面积是多少平方分米．
<gadget id="calculator">30 / 10</gadget>
<output>3</output>

<gadget id="calculator">1.2 / 2</gadget>
<output>0.6</output>

<gadget id="calculator">3 * 0.6</gadget>
<output>1.8</output>

<result>1.8</result>