In a math fun competition, there were 20 questions in total, 5 points for each correct answer, and 2 points deducted for missing or wrong answers. Yu Mei scored 86 points. How many questions did she answer correctly?
在一次数学趣味竞赛中，共有20道题，每答对一题得5分，不答或答错一题倒扣2分，于梅得了86分，她答对了几道题？
<gadget id="calculator">20 * 5</gadget>
<output>100</output>

<gadget id="calculator">100 - 86</gadget>
<output>14</output>

<gadget id="calculator">5 + 2</gadget>
<output>7</output>

<gadget id="calculator">14 / 7</gadget>
<output>2</output>

<gadget id="calculator">20 - 2</gadget>
<output>18</output>

<result>18</result>