Xiao Ming's scores in the first four math tests this semester are: 85 points, 76 points, 92 points, and 78 points. How many points should he take in the fifth test to make the average score of the five tests reach 85 points.
小明这学期数学前四次的测验成绩分别为：85分、76分、92分、78分，第五次测验时他要考多少分，才能使五次测验的平均成绩达85分．
<gadget id="calculator">85 * 5</gadget>
<output>425</output>

<gadget id="calculator">85 + 76 + 92 + 78</gadget>
<output>331</output>

<gadget id="calculator">425 - 331</gadget>
<output>94</output>

<result>94</result>