Grandma Zhang exercises her body and runs 5 laps around a square playground with a side length of 40 meters every day. How many meters does she run every day?
张奶奶锻炼身体，每天绕着边长为40米的正方形操场跑5圈，她每天跑多少米？
<gadget id="calculator">40 * 4 * 5</gadget>
<output>800</output>

<result>800</result>