The school playground is rectangular, 100 meters long and 50 meters wide. Once, during physical education class, I ran around the playground for 3 weeks. How many meters did I run in total?
学校操场是长方形的，长100米，宽50米，有一次上体育课时，绕操场跑了3周，共跑了多少米？
<gadget id="calculator">100 + 50</gadget>
<output>150</output>

<gadget id="calculator">150 * 2 * 3</gadget>
<output>900</output>

<result>900</result>