Mr. Li drove from Nanjing to Shanghai for a meeting. The total length is 288 kilometers. After driving for a while, there are still 114 kilometers left. Mr. Li drives an average of 58 kilometers per hour. How many hours has he been driving?
李老师开车从南京出发去上海开会，全长288千米，开了一段时间后还有114千米，李老师平均每小时行58千米，他已经开了几小时？
<gadget id="calculator">288 - 114</gadget>
<output>174</output>

<gadget id="calculator">174 / 58</gadget>
<output>3</output>

<result>3</result>