The school held a mathematics competition, with a total of 20 test questions, and 5 points were awarded for one correct answer. 3 points will be deducted for not doing or doing a wrong question. Xiaoxing scored 60 points. Guess how many questions he got right?
学校举行数学竞赛，共20道试题，做对一道得5分．没有做或做错一题倒扣3分．小星得了60分，猜猜他做对了几题？
<gadget id="calculator">20 * 5</gadget>
<output>100</output>

<gadget id="calculator">100 - 60</gadget>
<output>40</output>

<gadget id="calculator">3 + 5</gadget>
<output>8</output>

<gadget id="calculator">40 / 8</gadget>
<output>5</output>

<gadget id="calculator">20 - 5</gadget>
<output>15</output>

<result>15</result>