Divide a large square with a side length of 10 cm into 4 small squares, what is the perimeter of each small square in cm?
把一个边长为10厘米的大正方形平均分成4个小正方形，每个小正方形的周长是多少厘米．
<gadget id="calculator">10 / 2</gadget>
<output>5</output>

<gadget id="calculator">5 * 4</gadget>
<output>20</output>

<result>20</result>