Xiaoqiang's average score in mathematics in the past few times was 84 points, and this time he needs to take 100 points in the test to make the average score reach 86 points. This time is the first exam.
小强前几次数学平均成绩是84分，这次要考100分，才能使平均成绩达到86分．这一次是第多少次考试．
<gadget id="calculator">100 - 84</gadget>
<output>16</output>

<gadget id="calculator">86 - 84</gadget>
<output>2</output>

<gadget id="calculator">16 / 2</gadget>
<output>8</output>

<result>8</result>