A car travels 50 kilometers per hour from point A to point B, arrives in 3.2 hours, and travels 40 kilometers per hour when returning, how many hours does it take?
一辆汽车从甲地到乙地，每小时行50千米，3.2小时到达，返回时每小时行40千米，用了多少小时？
<gadget id="calculator">3.2 / 40</gadget>
<output>0.08</output>

<gadget id="calculator">50 * 0.08</gadget>
<output>4</output>

<result>4</result>