The area of a parallelogram billboard is 25 square meters, what is the area of another triangular billboard equal to its base and height.
一个平行四边形广告牌的面积是25㎡，另一块与它等底等高的三角形广告牌面积是多少．
<gadget id="calculator">25 / 2</gadget>
<output>25/2 = around 12.5</output>

<result>25/2 = around 12.5</result>