The path of a swimming pool is 50 meters long. Xiaojun swam 4 times in the path of this swimming pool. How many meters did he swim in total?
一个游泳池的池道长50米，小军在这个游泳池的池道中游了4个来回，他大约一共游了多少米．
<gadget id="calculator">50 * 2 * 4</gadget>
<output>400</output>

<result>400</result>