Li Ming and Xiao Wang Jun were running on the school's circular runway. They started from the same place and walked in opposite directions. Li Ming ran 2 meters per second, and Wang Jun ran 3 meters per second. After 1 minute and 20 seconds, the two met. What is the perimeter in meters?
李明和小王军在学校环形跑道上跑步，两人从同一地点出发，反向而行，李明每秒跑2米，王军每秒跑3米，经过1分20秒两人相遇，跑道的周长是多少米？
<gadget id="calculator">2 + 3</gadget>
<output>5</output>

<gadget id="calculator">5 * 80</gadget>
<output>400</output>

<result>400</result>