There are 10 questions in the math competition, 8 points are awarded for each correct question, 5 points are deducted for each incorrect question (or not done), Xiao Ming gets 41 points, how many questions did he get wrong (or not done) in total.
数学竞赛共10道题，做对一题得8分，做错一题(或不做)倒扣5分，小明得41分，他共做错(或不做)了多少道题．
<gadget id="calculator">10 * 8</gadget>
<output>80</output>

<gadget id="calculator">80 - 41</gadget>
<output>39</output>

<gadget id="calculator">8 + 5</gadget>
<output>13</output>

<gadget id="calculator">39 / 13</gadget>
<output>3</output>

<result>3</result>