A car drives from place A to place B at a constant speed, and the first 4 hours just traveled the entire distance (2/5). How many hours did it take the car to travel from A to B?
一辆汽车以不变的速度从甲地开往乙地，前4小时刚好行了全程的(2/5)．这辆汽车从甲地行驶到乙地共用了多少小时？
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">(2/5) / 4</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">1 / (1/10)</gadget>
<output>10</output>

<result>10</result>