The area of a triangle is 10 square decimeters, if the base is enlarged by 2 times and the height is reduced by 4 times, what is the current area in square decimeters?
一个三角形的面积为10平方分米，若底扩大2倍，高缩小4倍，则现在的面积为多少平方分米．
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">10 * (1/2)</gadget>
<output>5</output>

<result>5</result>