There were 25 questions in a certain mathematics competition. The scoring standard is: 4 points for each correct answer, and 2 points for each wrong answer or failure to answer a question. Xiao Ming participated in this math competition and scored 70 points. How many questions did you get right?
某次的数学竞赛共有25道题，评分标准是：每做对一题得4分，每做错或不做一题扣2分，小明参加了这次数学竞赛，得了70分，那么小明做对了几道题？
<gadget id="calculator">25 * 4</gadget>
<output>100</output>

<gadget id="calculator">100 - 70</gadget>
<output>30</output>

<gadget id="calculator">4 + 2</gadget>
<output>6</output>

<gadget id="calculator">30 / 6</gadget>
<output>5</output>

<gadget id="calculator">25 - 5</gadget>
<output>20</output>

<result>20</result>