Divide a rectangle into two squares without residue. The side length of the square is 4 cm. What is the perimeter of the rectangle in cm?
将一个长方形分成两个正方形而没有剩余，正方形的边长是4厘米，长方形的周长是多少厘米．
<gadget id="calculator">4 * 2</gadget>
<output>8</output>

<gadget id="calculator">8 + 4</gadget>
<output>12</output>

<gadget id="calculator">12 * 2</gadget>
<output>24</output>

<result>24</result>