A car goes to the county to deliver goods, and when it goes there, it travels 40 kilometers per hour and arrives in 6 hours; when it returns, it travels 60 kilometers per hour, how many hours can it arrive?
一辆汽车去县城送货，去时每小时行40千米，6小时到达；回时每小时行60千米，几小时可以到达？
<gadget id="calculator">40 * 6</gadget>
<output>240</output>

<gadget id="calculator">240 / 60</gadget>
<output>4</output>

<result>4</result>