The school playground is a rectangle with a length of 50 meters and a width of 25 meters. Xiaogang ran 4 laps along the playground, how many meters did he run in total?
学校操场是一个长50米，宽25米的长方形．小刚沿着操场跑了4圈，一共跑了多少米？
<gadget id="calculator">50 + 25</gadget>
<output>75</output>

<gadget id="calculator">75 * 2 * 4</gadget>
<output>600</output>

<result>600</result>