Xiao Ming participates in a singing competition. The scores of the seven judges are 98, 88, 90, 92, 83, 89 and 91. If the highest score and the lowest score are removed, what is Xiao Ming's average score?
小明参加歌咏比赛，7个评委的打分分别是98分、88分、90分、92分、83分、89分和91分，如果去掉一个最高分和一个最低分，小明的平均得分是多少？
<gadget id="calculator">88 + 90 + 92 + 89 + 91</gadget>
<output>450</output>

<gadget id="calculator">450 / 5</gadget>
<output>90</output>

<result>90</result>