Xiaohua stretched a rectangular wooden frame with a length of 15 cm and a width of 10 cm into a parallelogram. What is the perimeter of this parallelogram in centimeters.
小华把一个长15厘米、宽10厘米的长方形木框拉成了一个平行四边形．这个平行四边形的周长是多少厘米．
<gadget id="calculator">15 + 10</gadget>
<output>25</output>

<gadget id="calculator">25 * 2</gadget>
<output>50</output>

<result>50</result>