The length of a rectangle is 15 cm and the width is 10 cm. After drawing it into a parallelogram, what is the perimeter of the parallelogram in cm?
一个长方形的长是15厘米，宽是10厘米，把它拉成一个平行四边形后，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>