A passenger ship departs from Port A to Port B, plans to travel 28km per hour, and arrives in 12.5 hours. Due to the downwind during sailing, the actual driving is 7km per hour, so how many hours will it take to arrive?
一艘客轮从甲港出发开往乙港，计划每小时行驶28km，12.5小时可以到达．由于航行时顺风，实际每小时多行驶7km，这样需用几小时到达？
<gadget id="calculator">28 + 7</gadget>
<output>35</output>

<gadget id="calculator">12.5 / 35</gadget>
<output>0.357143</output>

<gadget id="calculator">28 * 0.357143</gadget>
<output>10.000004</output>

<result>10.000004</result>