The perimeter of a square is equal to the perimeter of a rectangle with a length of 7 cm and a width of 5 cm. What is the side length of the square in cm?
一个正方形的周长与一个长7厘米，宽5厘米的长方形周长相等，这个正方形的边长是多少厘米？
<gadget id="calculator">7 + 5</gadget>
<output>12</output>

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

<gadget id="calculator">12 * (1/2)</gadget>
<output>6</output>

<result>6</result>