The total score of the first five exams is 428 points. The average score of the sixth to ninth exams is 1.4 points more than the average score of the first five exams. Now the tenth exam is going to be conducted, so that the average score of the last five exams is higher than all What is the minimum test score for ten times?
前五次考试的总分是428分，第六次至第九次的平均分比前五次平均分多1.4分，现在要进行第十次考试，要使后五次的平均分高于所有十次至少要考几分？
<gadget id="calculator">428 / 5</gadget>
<output>428/5 = around 85.6</output>

<gadget id="calculator">(428/5) + 1.4</gadget>
<output>87</output>

<gadget id="calculator">87 * 4</gadget>
<output>348</output>

<gadget id="calculator">428 - 348</gadget>
<output>80</output>

<result>80</result>