The perimeter of a parallelogram is 68 cm, and the length of one side is 15 cm. What is the length of the side adjacent to this side?
一个平行四边形的周长是68厘米，它的一条边的长是15厘米，与这条边相邻的边的长是多少？
<gadget id="calculator">15 * 2</gadget>
<output>30</output>

<gadget id="calculator">68 - 30</gadget>
<output>38</output>

<gadget id="calculator">38 / 2</gadget>
<output>19</output>

<result>19</result>