A rectangle and a square have the same area. Given that the side length of the square is 20cm and the length of the rectangle is 25cm, find the width of the rectangle. (solution by equation)
一个长方形和一个正方形的面积相等．已知正方形的边长是20cm，长方形的长是25cm，求长方形的宽．(用方程解)
<gadget id="calculator">20 * 20</gadget>
<output>400</output>

<gadget id="calculator">400 / 25</gadget>
<output>16</output>

<result>16</result>