The perimeter of a rectangle is equal to the perimeter of a square. The side length of the square is 8 cm. The length of the rectangle is 12 cm. What is the width in cm?
一个长方形的周长与一个正方形的周长相等，已知正方形的边长是8cm，长方形的长是12cm，宽是多少cm？
<gadget id="calculator">4 / 2</gadget>
<output>2</output>

<gadget id="calculator">8 * 2</gadget>
<output>16</output>

<gadget id="calculator">16 - 12</gadget>
<output>4</output>

<result>4</result>