The naughty family drove to Beijing during the May Day holiday. The speed of the car was 90.5 kilometers per hour, and it took 4.5 hours to reach the destination. How many kilometers did they walk in total?
淘气全家五一假期开车去北京游玩，车速90.5千米/小时，行驶了4.5小时到达目的地，算一算他们共走了多少千米？
<gadget id="calculator">90.5 * 4.5</gadget>
<output>407.25</output>

<result>407.25</result>