70) what is the value of x?

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70) what is the value of x?

by ern5231 » Wed May 12, 2010 4:58 am
Five integers 2,4,8,10,x. What is the value of x?
1) x not equal to 16
2) Median is equal to mean

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by November Rain » Wed May 12, 2010 5:45 am
Hi,

Is it B?

The only way the median is equal to the mean is if the set contains evenly spaced numbers.

Since the set contains all even numbers from 2 to 10, but skips the 6, then X = 6

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by vcb » Wed May 12, 2010 6:53 am
so 6 is a probable answer.. What if x=-4?

The average would then be 4: (-4+2+4+8+10)/5 = 4; The median too would be +4. So we have two different answers. Wat say?

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by liferocks » Wed May 12, 2010 7:37 am
Clearly 1 is not sufficient
form 2

mean =24+x/5

if x<2..median =4hence 4=24+x/5 or x=-4
if x>11..median 8..hence 8=24+x/5 or x=16
since mean=median 24+x must be divisible by 5..hence only possible value of x such that 2<x<10 is x=6 and mean is 6
...all these are possible..hence not sufficient

combining x is either -4 or 6...not sufficient

IMO ans option E
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by gmatmachoman » Wed May 12, 2010 8:06 am
vcb wrote:so 6 is a probable answer.. What if x=-4?

The average would then be 4: (-4+2+4+8+10)/5 = 4; The median too would be +4. So we have two different answers. Wat say?

yeah u r correct!! Pick E

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by iamseer » Wed May 12, 2010 8:21 am
November Rain wrote: The only way the median is equal to the mean is if the set contains evenly spaced numbers.
If the set is evenly spaced, mean=median

But the reverse is not necessarily true. Example of this is in one of the explanations above. (-4,2,4,8,10) mean=median=4 but the set is not evenly spaced.
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