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In a set of consecutive ODD integers, the mean ALWAYS equals
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01 Apr 2015, 20:21
Hi All,
While this post originally goes back to 2007, and most (if not all) of the posters are probably gone, the questions posed are essentially Number Properties. They can ALL be proven by TESTing VALUES, although it does not appear that anyone went to the trouble of proving what they believed.
Here is the proof:
1) In a set of consecutive ODD integers, the mean ALWAYS equals the median.
Here are a series of examples to prove that this is TRUE.
{1, 3}
Mean = (1+3)/2 = 2
Median = (1+3)/2 = 2
Mean = Median
{1, 3, 5}
Mean = (1+3+5)/3 = 3
Median = 3
Mean = Median
{-3, -1, 1, 3}
Mean = (-3-1+1+3)/4 = 0
Median = (-1+1)/2 = 0
Mean = Median
{-5, -3, -1, 1, 3}
Mean = (-5-3-1+1+3)/5 = -1
Median = -1
Mean = Median
Using similar methods, you can also prove that the following is true:
2) In a set of consecutive EVEN integers, the mean ALWAYS equals the median.
GMAT assassins aren't born, they're made,
Rich