Xiaogang went for a walk, and saw the first street light after walking 10 meters, and then he could see a street light every 10 meters. How many meters has he traveled when he reaches the 20th street light?
小刚去散步，走10米后看到了第一盏路灯，接着他每走10米都能看到一盏路灯．当他走到第20盏路灯时，他已经走了多少米？
<gadget id="calculator">20 * 10</gadget>
<output>200</output>

<result>200</result>