作业帮一道SAT数学题目,要详细解答3,4,6,7,10,12The number n is to be added to the list above. If n is an integer, which of the following could be median of the new list of seven numbers?I. 6II. 6.5III. 7A I onlyB II onlyC III onlyD I and II onlyE
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一道SAT数学题目,要详细解答3,4,6,7,10,12The number n is to be added to the list above. If n is an integer, which of the following could be median of the new list of seven numbers?I. 6II. 6.5III. 7A I onlyB II onlyC III onlyD I and II onlyE
一道SAT数学题目,要详细解答
3,4,6,7,10,12
The number n is to be added to the list above. If n is an integer, which of the following could be median of the new list of seven numbers?
I. 6
II. 6.5
III. 7
A I only
B II only
C III only
D I and II only
E I, II, and III
一道SAT数学题目,要详细解答3,4,6,7,10,12The number n is to be added to the list above. If n is an integer, which of the following could be median of the new list of seven numbers?I. 6II. 6.5III. 7A I onlyB II onlyC III onlyD I and II onlyE
我怎么觉得答案是1和3 only呢.
7个数字的数列,中位数只可能是数列里面的数字,那么6.5就不可能了
然后当n小于或等于6的时候,中位数是6
当n大于或等于7的时候,中位数是7
C III only
3,4,6,7,10,12六个的和是42，42/7=6，所以(42+n)/7一定大于6，A错。
假设6.5正确，6.5*7=45.5，此时n=3.5非整数，B错
当n=7时，平均数正好=7，符合题意
the answer could be wrong, since only I and III are possible.
median means the number listed in the middle of the sequence; if either 6 or 7 be added to the list, 6 or 7 is exactly the median of t...
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the answer could be wrong, since only I and III are possible.
median means the number listed in the middle of the sequence; if either 6 or 7 be added to the list, 6 or 7 is exactly the median of the list, since n is an integer.
if no extra numbers are added to the list, then 6.5 is the median, since there are an even number of items in the list, which means you need to take the average of the middle two numbers to make the median.
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我个人感觉你题目写错了，你随便选个小等于6的整数放进去中位数是7，你选个大等于7的整数放进去中位数是6所以I和III是对的，可是你选项里面没有。6.5是不可能的……