Zhao Liang and his father and mother went on a trip and took the train round trip. Each ticket was 168 yuan. How much did they spend on the train tickets for this trip?
赵亮和爸爸、妈妈去旅游，往返都乘火车，每张车票168元，这次旅游买火车票一共花了多少钱？
<gadget id="calculator">168 * 3 * 2</gadget>
<output>1_008</output>

<result>1_008</result>