Yucai Primary School held a mathematics competition. There were 20 test questions in total. 5 points were awarded for one correct question, and 3 points were deducted for one wrong question. Xiaohua scored 84 points. How many questions did he get right?
育才小学举行数学竞赛，共20道试题，做对一道题得5分，做错一道题倒扣3分，小华得了84分，他做对了几道题？
<gadget id="calculator">5 * 20</gadget>
<output>100</output>

<gadget id="calculator">100 - 84</gadget>
<output>16</output>

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

<gadget id="calculator">16 / 8</gadget>
<output>2</output>

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

<result>18</result>