A parallelogram with a base of 18cm and a height of 11cm is nailed by four wooden strips. After stretching it into a rectangle, the area increases by 36cm**2. What is the width of the rectangle in cm.
由四根木条钉成的一个底是18cm，高是11cm的平行四边形，把它拉成长方形后，面积增加了36cm**2．长方形的宽是多少cm．
<gadget id="calculator">18 * 11</gadget>
<output>198</output>

<gadget id="calculator">198 + 36</gadget>
<output>234</output>

<gadget id="calculator">234 / 18</gadget>
<output>13</output>

<result>13</result>