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 Author: Gennadiy [ Sun Aug 18, 2013 7:06 am ] Post subject: Re: GMAT Algebra questioner wrote:The correct answer should be 29 instead of 28: 15 - (-13) + 1, because 15 and -13 are both in the range inclusive.15 and -13 are the maximum and minimum elements indeed, so to calculate the range (the difference between the largest and the smallest numbers in a set) we do not need to add 1, it is just 15 – (-13) = 28 .Here is an example of applying the formula to a non-integer values:{-3.5, -2, 0.5, 4.3}The range is 4.3 – (-3.5) = 7.8The minimum element is not necessarily negative,{2.5, 7, 15.4, 16.9}The range is 16.9 – 2.5 = 14.4As also the maximum element is not necessarily positive,{-6, -3.1, -2.5}The range is -2.5 – (-6) =3.5However, remember, that range is always positive or zero (in case when all elements are the same).

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