Re: First of all, this is a terrific forum. Good discussions.
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17 Sep 2004, 07:26
The Answer is C.
Statement 1 tells us that the difference between any two integers in the set is less than 3. This information alone yields a variety of possible sets.
For example, one possible set (in which the difference between any two integers is less than 3) might be:
(x, x, x, x + 1, x + 1, x + 2, x + 2)
Mode = x (as stated in question stem)
Median = x + 1
Difference between median and mode = 1
Alternately, another set (in which the difference between any two integers is less than 3) might look like this:
(x – 1, x, x, x + 1)
Mode = x (as stated in the question stem)
Median = x
Difference between median and mode = 0
We can see that statement (1) is not sufficient to determine the difference between the median and the mode.
Statement (2) tells us that the average of the set of integers is x. This information alone also yields a variety of possible sets.
For example, one possible set (with an average of x) might be:
(x – 10, x, x, x + 1, x + 2, x + 3, x + 4)
Mode = x (as stated in the question stem)
Median = x + 1
Difference between median and mode = 1
Alternately, another set (with an average of x) might look like this:
(x – 90, x, x, x + 15, x + 20, x + 25, x + 30)
Mode = x (as stated in the question stem)
Median = x + 15
Difference between median and mode = 15
We can see that statement (2) is not sufficient to determine the difference between the median and the mode.
Both statements taken together imply that the only possible members of the set are x – 1, x, and x + 1 (from the fact that the difference between any two integers in the set is less than 3) and that every x – 1 will be balanced by an x + 1 (from the fact that the average of the set is x). Thus, x will lie in the middle of any such set and therefore x will be the median of any such set.
If x is the mode and x is also the median, the difference between these two measures will always be 0.
The correct answer is C: BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.