Wang Simin participated in a mathematics competition. There were 20 competition questions in the whole volume. 5 points were awarded for a correct answer, and 3 points were deducted for an incorrect answer. Wang Simin did all the questions and got 68 points in total. How many questions did he get right?
王思敏参加一次数学竞赛，全卷共20道竞赛题，做对一道得5分，做错一道倒扣3分．王思敏道题都做了，共得68分，他做对了几题？
<gadget id="calculator">20 * 5</gadget>
<output>100</output>

<gadget id="calculator">100 - 68</gadget>
<output>32</output>

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

<gadget id="calculator">32 / 8</gadget>
<output>4</output>

<gadget id="calculator">20 - 4</gadget>
<output>16</output>

<result>16</result>