car drives from place A to place B. It takes 5 hours to drive about 80 kilometers per hour, and it only takes 4 hours to return. What is the speed of the car when it returns?
一辆汽车从甲地开往乙地，每小时行驶约80千米，用了5小时，返回时只用4小时，这辆汽车返回时速度是多少．
<gadget id="calculator">5 / 4</gadget>
<output>5/4 = around 1.25</output>

<gadget id="calculator">80 * (5/4)</gadget>
<output>100</output>

<result>100</result>