median/mean - Set A consists of 5 positive integers

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Set A consists of 5 positive integers. What is the range of Set A?
(1) The median of Set A is 2 greater than the average (arithmetic mean) of Set A
(2) The greatest integer is 8
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by dmateer25 » Wed Jan 14, 2009 8:13 am
(1) The median of Set A is 2 greater than the average (arithmetic mean) of Set A
mean = x
median = x + 2

Lets say

x=10
x+ 2 = 12

so the total of the 5 numbers needs to be 50 and include 12.

1 + 2 + 12 + 15 + 20 = 50

Mean = 10
Median = 12
Range = 19

Lets say x = 6
x+2 = 8

Total of the numbers will be 30 and include 8.
1 + 2 + 8 + 9 + 10

Mean = 6
Median =8
Range = 9

INSUFF


a + b +c +d +e/2 = x
a+ b + x + 2 +e/2 = x


(2) The greatest integer is 8

if the smallest integer is 1 then the range is 7
if the smallest integer is 2 then the range is 6

INSUFF


Together

(a + b +(x + 2) + d + 8)/2 = x

1 + 2 + 7 + 7 + 8
mean = 5
median =7
range = 7

2 + 4 + 8 + 8 + 8
mean = 6
median = 8
range = 6

INSUFF

I choose E.
Last edited by dmateer25 on Wed Jan 14, 2009 11:35 am, edited 1 time in total.

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by Brent@GMATPrepNow » Wed Jan 14, 2009 8:24 am
The answer is E.
Great work - awesome solution
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by logitech » Wed Jan 14, 2009 11:32 am
dmateer25 is the man!

I am still trying to find a GMAT solution.
LGTCH
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by cramya » Wed Jan 14, 2009 5:38 pm
Dmateer,
Good solution!!!


Brent,
Whats ur solution to this? I always find these statictics DS take up more time since we have to come up yes/no answers wherever possible by picking numbers.

Attacking these conceptaully seems to be a more harder task almost out of question..... IMO

Regards,
CR