The circular runway of the school playground is 250 meters long. Xiao Gang and Xiao Rong start from the same place and walk in opposite directions. Xiaogang runs 4 meters per second, and Xiao Rong runs 1 meter per second. How many seconds will it take for the two to meet?
学校操场的环行跑道长250米，小刚和小蓉从同一地点出发，反向而行．小刚每秒跑4米，小蓉每秒跑1米，经过多少秒后两人相遇？
<gadget id="calculator">4 + 1</gadget>
<output>5</output>

<gadget id="calculator">250 / 5</gadget>
<output>50</output>

<result>50</result>