fozzzy wrote:
S is a set containing 9 different numbers. T is a set containing 8 different numbers, all of which are members of S. which of the following statements cannot be true?
A) The mean of S is equal to the mean of T
B) The median of S is equal to the median of T
C) The range of S is equal to the range of T
D) The mean of S is greater than the mean of T
E) The range of S is less than the range of T
Detailed explanation will be appreciated. Thanks!
Mean of both the sets can be equal. Let us suppose the mean of any 8 number is 10 then the 9th number could also be 10 and mean remains the same.
In the same way median can also be same. In set of 9 numbers median will be the 5th number when arranged in ascending order and in set T it will be the mean of 4th and 5th number.
If we take S = { 1, 2, 3, 4 ,5, 6, 7, 8, 9 } and T as { 1, 2, 3, 4, 6, 7, 8, 9 } then median in both the cases will be 5.
From the above eg range is same in both the cases.
If the number which is not the part of set T is greater than mean of T then the mean of set S will be greater than that of set T
Range of S will always be greater than or equal to range of T because of an additional number. If that number is greater than the greatest number in set T the range will be more, if that number is smaller than the smallest number in set T again the range will be more since now the new number is the smallest number. If that number lies in between then the range will be equal.
If you like my explanation please give a kudo.