Naughty and Xiaoxiao walk from the same point on the playground in opposite directions along the periphery of the playground at the same time. Naughty walks 75 meters per minute, and Xiaoxiao walks 65 meters per minute. They meet each other in 5 minutes. What is the perimeter of the school playground in meters?
淘气和笑笑从操场的同一点同时向相反方向沿操场外围走，淘气每分钟走75米，笑笑每分钟走65米，5分钟相遇，学校操场的周长是多少米？
<gadget id="calculator">75 + 65</gadget>
<output>140</output>

<gadget id="calculator">140 * 5</gadget>
<output>700</output>

<result>700</result>