4 identical triangles form a parallelogram. It is known that the area of the parallelogram is 40cm**2 and the height is 4cm, so how many centimeters is the base of each triangle?
4个完全一样的三角形拼成一个平行四边形．已知平行四边形的面积是40cm**2，高是4cm，那么每个三角形的底是多少厘米？
<gadget id="calculator">40 / 4</gadget>
<output>10</output>

<gadget id="calculator">2 / 4</gadget>
<output>1/2 = around 0.5</output>

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

<result>5</result>