Make the largest triangle on a semicircular steel plate with a diameter of 10 decimeters, what is the area of this triangle in square decimeters?
在一个直径是10分米的半圆形钢板上做一个最大的三角形，这个三角形的面积是多少平方分米．
<gadget id="calculator">10 / 2</gadget>
<output>5</output>

<gadget id="calculator">5 / 2</gadget>
<output>5/2 = around 2.5</output>

<gadget id="calculator">10 * (5/2)</gadget>
<output>25</output>

<result>25</result>