If two adjacent sides of a parallelogram are 17 cm and 10 cm long, what is the perimeter of the parallelogram in cm?
一个平行四边形两条相邻的边分别长17厘米和10厘米，这个平行四边形的周长是多少厘米．
<gadget id="calculator">17 + 10</gadget>
<output>27</output>

<gadget id="calculator">27 * 2</gadget>
<output>54</output>

<result>54</result>