There are 30 questions, 5 points for a correct answer and 3 points for a wrong answer. Xiao Ming gets 86 points in total. How many questions did he answer correctly?
有30道题，对一题得5分，错一题扣3分，小明共得86分，他答对了多少题．
<gadget id="calculator">30 * 5</gadget>
<output>150</output>

<gadget id="calculator">150 - 86</gadget>
<output>64</output>

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

<gadget id="calculator">64 / 8</gadget>
<output>8</output>

<gadget id="calculator">30 - 8</gadget>
<output>22</output>

<result>22</result>