A rope can be folded into a rectangle with a length of 13.2 cm and a width of 9.6 cm. If the rope is straightened, it can be folded into a square. What is the side length of the square in centimeters?
用一根绳子能正好折成一个长13.2厘米，宽9.6厘米的长方形，用这根绳子拉直，再折成一个正方形，这个正方形的边长是多少厘米？
<gadget id="calculator">13.2 + 9.6</gadget>
<output>22.8</output>

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

<gadget id="calculator">22.8 * (1/2)</gadget>
<output>11.4</output>

<result>11.4</result>