If a square with a side length of 10 decimeters is cut into two identical rectangles, the sum of the perimeters of the two rectangles will increase by how many centimeters compared with the original square.
一个边长是10分米的正方形剪成两个相同的长方形，两个长方形的周长之和比原来正方形增加了多少厘米．
<gadget id="calculator">10 * 2</gadget>
<output>20</output>

<result>20</result>