There are 158 cars in the parking lot. After one hour, only 128 cars are in the parking lot. Ask what percentage of the original total number of cars were driven away?
停车场有158辆汽车，一个小时后，只有128辆汽车在停车场．问开走的汽车占原总汽车辆的几分之几？
<gadget id="calculator">158 - 128</gadget>
<output>30</output>

<gadget id="calculator">30 / 158</gadget>
<output>15/79 = around 0.189873</output>

<result>15/79 = around 0.189873</result>