A circular fountain has a radius of 10 meters. Grandpa Li walks around the fountain 4 times a day. How many meters does Grandpa Li walk around the fountain every day?
一个圆形喷泉半径是10米，李爷爷每天绕这个喷泉散步走4圈，李爷爷每天绕喷泉走多少米？
<gadget id="calculator">2 * 3.14 * 10 * 4</gadget>
<output>251.2</output>

<result>251.2</result>