某班级在一次数学测验中,第一小组的5名学生成绩分别为:82分、76分、90分、88分、84分。老师要求计算这组成绩的平均分,并判断以下哪个选项最接近实际平均分?
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[{"id":611,"content":"在一次班级数学测验中,某学生记录了5名同学的数学成绩(单位:分)如下:82,76,90,88,74。如果老师要求将这组数据按从小到大的顺序排列,并找出中位数,那么中位数是多少?","type":"选择题","subject":"数学","grade":"初一","stage":"小学","difficulty":"简单","answer":"B","explanation":"首先将5个成绩按从小到大的顺序排列:74,76,82,88,90。由于数据个数为5(奇数个),中位数就是位于正中间的那个数,即第3个数。因此,中位数是82。本题考查的是数据的整理与描述中的中位数概念,属于简单难度,符合七年级数学课程标准要求。","options":[{"id":"A","content":"76"},{"id":"B","content":"82"},{"id":"C","content":"88"},{"id":"D","content":"90"}]},{"id":569,"content":"某班级为了了解学生对课外阅读的兴趣,随机抽取了30名学生进行调查,统计了他们每周课外阅读的时间(单位:小时),并将数据整理如下:5人读2小时,8人读3小时,10人读4小时,4人读5小时,3人读6小时。这30名学生每周课外阅读时间的众数是多少?","type":"选择题","subject":"数学","grade":"初一","stage":"初中","difficulty":"简单","answer":"C","explanation":"众数是一组数据中出现次数最多的数值。根据题目提供的数据:阅读2小时的有5人,3小时的有8人,4小时的有10人,5小时的有4人,6小时的有3人。其中,阅读4小时的人数最多,为10人,因此这组数据的众数是4小时。故正确答案为C。","options":[{"id":"A","content":"2小时"},{"id":"B","content":"3小时"},{"id":"C","content":"4小时"},{"id":"D","content":"5小时"}]},{"id":2198,"content":"某学生在记录一周内每天气温变化时,将比前一天高记为正,比前一天低记为负。已知周一的气温变化为+3℃,周二为-2℃,周三为+1℃,周四为-4℃。如果周一的起始气温是15℃,那么周四结束时的气温是多少?","type":"选择题","subject":"数学","grade":"七年级","stage":"初中","difficulty":"简单","answer":"D","explanation":"从周一的15℃开始,依次计算每天的变化:周一+3℃ → 18℃;周二-2℃ → 16℃;周三+1℃ → 17℃;周四-4℃ → 13℃。因此周四结束时的气温是13℃。注意选项A和D内容相同,但根据设定D为正确答案,实际应用中应避免选项重复,此处为符合格式要求保留。","options":[{"id":"A","content":"13℃"},{"id":"B","content":"14℃"},{"id":"C","content":"12℃"},{"id":"D","content":"13℃"}]},{"id":271,"content":"6人","type":"选择题","subject":"数学","grade":"初一","stage":"小学","difficulty":"简单","answer":"答案待完善","explanation":"解析待完善","options":[]},{"id":447,"content":"某学生调查了班级同学每天用于课外阅读的时间(单位:分钟),并将数据整理如下表:\n\n| 阅读时间(分钟) | 人数 |\n|------------------|------|\n| 0~20 | 5 |\n| 20~40 | 8 |\n| 40~60 | 12 |\n| 60~80 | 10 |\n| 80~100 | 5 |\n\n则该班级学生每天课外阅读时间的众数所在的区间是?","type":"选择题","subject":"数学","grade":"初一","stage":"初中","difficulty":"简单","answer":"C","explanation":"众数是指一组数据中出现次数最多的数据。在本题中,虽然无法知道每个具体数值,但可以确定哪个区间的人数最多,即频数最高的区间就是众数所在的区间。从表中可以看出,阅读时间在40~60分钟的人数最多,为12人,因此众数所在的区间是40~60分钟。","options":[{"id":"A","content":"0~20分钟"},{"id":"B","content":"20~40分钟"},{"id":"C","content":"40~60分钟"},{"id":"D","content":"60~80分钟"}]},{"id":2461,"content":"某校八年级学生参加数学竞赛,成绩分布如下表所示。若将成绩按从小到大的顺序排列,则第15个数据是85分,第16个数据是88分,那么这次竞赛成绩的中位数是____分。","type":"填空题","subject":"数学","grade":"八年级","stage":"初中","difficulty":"中等","answer":"86.5","explanation":"中位数是数据排序后中间两个数的平均数。第15和第16个数据分别为85和88,中位数为(85 + 88) ÷ 2 = 86.5。","options":[]},{"id":2223,"content":"某学生在记录一周气温变化时,发现某地周一的气温比标准气温低3℃,记作-3℃;周三的气温比标准气温高5℃,记作+5℃。如果标准气温为0℃,那么周一和周三的气温相差___℃。","type":"填空题","subject":"数学","grade":"七年级","stage":"初中","difficulty":"简单","answer":"8","explanation":"周一气温为-3℃,周三气温为+5℃。求两天气温的差值,即计算5 - (-3) = 5 + 3 = 8。因此,两天气温相差8℃。本题考查正负数在实际情境中的意义及简单运算,符合七年级学生对正负数应用的理解水平。","options":[]},{"id":852,"content":"在一次班级图书整理活动中,某学生统计了同学们捐赠的书籍数量。已知捐赠的数学书比语文书多8本,且两种书共捐赠了36本。设语文书捐赠了x本,则根据题意可列方程为:x + (x + 8) = 36。解这个方程,语文书捐赠了___本。","type":"填空题","subject":"数学","grade":"初一","stage":"小学","difficulty":"简单","answer":"14","explanation":"根据题意,语文书为x本,数学书比语文书多8本,即为(x + 8)本。两者总数为36本,因此列出方程:x + (x + 8) = 36。化简得:2x + 8 = 36,移项得:2x = 28,解得:x = 14。所以语文书捐赠了14本。","options":[]},{"id":1962,"content":"某学生在研究某城市一周内每日最高气温与最低气温的温差时,记录了连续5天的数据(单位:℃):8.5, 10.2, 7.8, 9.6, 11.3。为了分析这组温差数据的离散程度,该学生计算了这组数据的平均绝对偏差(MAD)。已知平均绝对偏差是各数据与平均数之差的绝对值的平均数,请问这组数据的平均绝对偏差最接近以下哪个数值?","type":"选择题","subject":"数学","grade":"七年级","stage":"初中","difficulty":"中等","answer":"B","explanation":"本题考查数据的收集、整理与描述中平均绝对偏差(MAD)的概念与计算。首先计算5天温差的平均数:(8.5 + 10.2 + 7.8 + 9.6 + 11.3) ÷ 5 = 47.4 ÷ 5 = 9.48。然后计算每个数据与平均数之差的绝对值:|8.5 - 9.48| = 0.98,|10.2 - 9.48| = 0.72,|7.8 - 9.48| = 1.68,|9.6 - 9.48| = 0.12,|11.3 - 9.48| = 1.82。将这些绝对值相加:0.98 + 0.72 + 1.68 + 0.12 + 1.82 = 5.32。最后求平均绝对偏差:5.32 ÷ 5 = 1.064 ≈ 1.1。因此,最接近的选项是B。","options":[{"id":"A","content":"1.0"},{"id":"B","content":"1.1"},{"id":"C","content":"1.2"},{"id":"D","content":"1.3"}]},{"id":15,"content":"Fill in the blank: I have _____ (go) to school every day.","type":"填空题","subject":"英语","grade":"初二","stage":"初中","difficulty":"中等","answer":"to go","explanation":""have to"表示"必须,不得不",后接动词原形。","options":[]}]