A car travels at a speed of about 80 km/h. It takes 5 hours to drive from A to B, and it takes 1 hour less to return. What is the speed of this car when it returns?
一辆汽车速度约为80千米/小时，从甲地开往乙地，用了5小时，返回时少用了1小时，这辆汽车返回时的速度是多少？
<gadget id="calculator">5 - 1</gadget>
<output>4</output>

<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>