Xiaojun has participated in three math competitions, with an average score of 84. It is known that the average score of the first two is 85. How many points did she get in the third time?
小军参加3次数学竞赛，平均分是84分，已知前两次平均分是85分，她第三次得了多少分．
<gadget id="calculator">84 * 3</gadget>
<output>252</output>

<gadget id="calculator">85 * 2</gadget>
<output>170</output>

<gadget id="calculator">252 - 170</gadget>
<output>82</output>

<result>82</result>