A fishing boat travels 20 kilometers per hour when sailing downstream and 14 kilometers per hour when sailing upstream. What is the speed of the ship in kilometers.
一只渔船顺水航行每小时行20千米，逆水航行每小时行14千米．船的速度是多少千米．
<gadget id="calculator">20 - 14</gadget>
<output>6</output>

<gadget id="calculator">6 / 2</gadget>
<output>3</output>

<result>3</result>