Nail it into a rectangular frame with thin wooden strips. The length is 10 decimeters and the width is 50 centimeters. If it is drawn into a parallelogram, what is its perimeter?
用细木条钉成一个长方形框．长10分米，宽50厘米，如果把它拉成一个平行四边形，它的周长是多少分米．
<gadget id="calculator">50 / 10</gadget>
<output>5</output>

<gadget id="calculator">10 + 5</gadget>
<output>15</output>

<gadget id="calculator">15 * 2</gadget>
<output>30</output>

<result>30</result>