There were 10 questions in a certain mathematics competition. It was stipulated that answering one question correctly would get 10 points, and each wrong answer or no answer would deduct 3 points. Liangliang answered all the questions and scored 61 points. How many questions did he get wrong?
某次数学竞赛10道题，规定答对一道题得10分，答错或不答每道扣3分，亮亮将题全部答完，结果得了61分，他答错了几道题？
<gadget id="calculator">10 * 10</gadget>
<output>100</output>

<gadget id="calculator">100 - 61</gadget>
<output>39</output>

<gadget id="calculator">10 + 3</gadget>
<output>13</output>

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

<result>3</result>