Help needed Experts pls!

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Help needed Experts pls!

by srini1988 » Tue Aug 02, 2011 4:29 am
Nine positive integers are contained in set N.The median of the set N is the integer x. and all the values in the set N are 3x or smaller.What is the largest possible average of set N.

I x
II 17x/9
III (17x/9) - 1
IV (17x-4)/9
V 3x
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by Frankenstein » Tue Aug 02, 2011 4:45 am
Hi,
Let the 9 integers be t1,t2,...,t9 when placed in an increasing order.
So, t1<=t2<=...t5<=...<=t9
median is x.
So, t5 = x
For the sum of integers to be maximum, each of the terms should take maximum possible value.
So, t1=t2=...=t5 = x
and t6=t7=t8=t9= 3x
So, avg is [5(x)+4(3x)]/9 = 17x/9
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