Hongqi Primary School held a knowledge contest. There were 10 questions in the test. For each correct answer, 10 points were awarded, and 5 points were deducted for each wrong answer. Xiaoli finally got 70 points. How many questions did he answer correctly?
红旗小学举行知识竞赛，试题共10题，每答对一题得10分，答错一题倒扣5分，小力最后得70分，他一共答对了多少道题．
<gadget id="calculator">10 * 10</gadget>
<output>100</output>

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

<gadget id="calculator">10 + 5</gadget>
<output>15</output>

<gadget id="calculator">30 / 15</gadget>
<output>2</output>

<gadget id="calculator">10 - 2</gadget>
<output>8</output>

<result>8</result>