There are 25 questions in the primary school mathematics competition in Nancheng District. If you answer a question correctly, you get 8 points, and if you get a wrong question, 4 points will be deducted. Li Ming did 15 questions and got 72 points in total. How many questions did he get right?
南城区的小学数学竞赛题共25道，做对一题得8分，做错一题倒扣4分，不做不记分，也不扣分．李明做了15道题共得72分，他做对了多少道题．
<gadget id="calculator">15 * 8</gadget>
<output>120</output>

<gadget id="calculator">120 - 72</gadget>
<output>48</output>

<gadget id="calculator">8 + 4</gadget>
<output>12</output>

<gadget id="calculator">48 / 12</gadget>
<output>4</output>

<gadget id="calculator">15 - 4</gadget>
<output>11</output>

<result>11</result>