Li Dong participates in swimming competitions and has to swim 8 rounds each time. This swimming pool is 50 meters long. How many meters does he have to swim each time?
李冬参加游泳比赛，每次要游8个来回，这个游泳池长50米，他每次要游多少米？
<gadget id="calculator">8 * 2</gadget>
<output>16</output>

<gadget id="calculator">50 * 16</gadget>
<output>800</output>

<result>800</result>