The Experimental Primary School held an environmental protection knowledge contest, with a total of 20 questions, 8 points for a correct answer, 5 points for a wrong answer, and 0 points for not answering the question. Chen Feiyang scored 123 points. How many questions did he answer correctly?
实验小学举行环保知识竞赛，一共20题，答对一题得8分，答错一题扣5分，没有回答该题0分，陈飞扬得了123分，他答对了多少道题．
<gadget id="calculator">20 - 1 - 3</gadget>
<output>16</output>

<result>16</result>