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RECRUITS

by adssaini » Fri Aug 07, 2009 8:35 am
can anybody explain this ?

OA : C
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by srisanj4 » Fri Aug 07, 2009 7:55 pm
In this question we need to know the cut off score below which recruiters have to retest. We know it is bottom 16%. We also know average of the scores = 72

Stem 1) we know population (500). This will not help determine the distribution nor the lowest or highest score. We cannot determine which population if any is pulling the average score. Not sufficient

Stem 2) we know 10 recruiters scored above average (actually above 82)... but again do not know what is the max score.. Not sufficient

Combined, we know out of 500, 10 scored higher than 82.. with this we cannot determine what is the bottom 16% score. Not sufficient

Answer is E

Am I correct? This seems too easy. which means a trap

:cry:

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by madhur_ahuja » Fri Aug 07, 2009 9:01 pm
I don't understand what is meant by normally distributed ... Can somebody explain ?

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by real2008 » Mon Aug 10, 2009 11:29 am
any body else there?

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by prindaroy » Wed Aug 12, 2009 12:59 pm
The answer could be C however it seems a little complicated. If only 10 recruits scored about 82 then, 10/500 = 2% scored above 82 or they are in the 98th percentile. We need to find score for 16th percentile. The score for 98th percentile as we have determined in 82. Now since the mean is 72, it's the 50th percentile. So 98 - 50 = 48 difference for a score of 10 points. Then we know the difference between 50 and 16 is 34. So solving for the number of points in a 34th percentile difference we get 170/24 points which is roughly equal to 7. So I would say the score would be about 65.
Last edited by prindaroy on Wed Aug 12, 2009 1:06 pm, edited 2 times in total.

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by niraj_a » Wed Aug 12, 2009 1:03 pm
won't B be good to go? the stem says "normally" distributed and bottom 16% = retest, which means 68% confidence interval.

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by prindaroy » Wed Aug 12, 2009 1:06 pm
Well the 68% confidence interval would not tell us much without the total number of recruits right?

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by niraj_a » Wed Aug 12, 2009 3:41 pm
yeah, i guess that's needed afterall.