Xiaoqiang's average score in the previous math tests was 84 points. This time, he needs to score 100 points in the test to raise his average score to 86 points. How many times is this the first test?
小强前几次数学测验的平均成绩是84分，这一次测验要得100分，才能把平均成绩提高到86分．这一次是第几次测验？
<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>