It takes 9 hours for a ship to sail 80 kilometers downstream and 48 kilometers upstream; it takes 12 hours to sail 64 kilometers downstream and 96 kilometers upstream. Find the speed of the boat in still water.
一艘轮船顺流航行80千米，逆流航行48千米共用9时；顺流航行64千米，逆流航行96千米共用12时．求轮船在静水中的速度．
<gadget id="calculator">160 - 64</gadget>
<output>96</output>

<gadget id="calculator">96 / 6</gadget>
<output>16</output>

<gadget id="calculator">80 / 16</gadget>
<output>5</output>

<gadget id="calculator">9 - 5</gadget>
<output>4</output>

<gadget id="calculator">48 / 4</gadget>
<output>12</output>

<gadget id="calculator">16 + 12</gadget>
<output>28</output>

<gadget id="calculator">28 / 2</gadget>
<output>14</output>

<result>14</result>