Another weighted average problem ?

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Another weighted average problem ?

by anuptvm » Wed Dec 29, 2010 5:34 am
Of the 800 employees in company X, 70 percent have been in the company for over 10 years. If y of these "long term" employees were to retire and no other employee changes were to occur, what value of y would reduce the percent of "long term" employees in the company to 60 percent?
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by anuptvm » Wed Dec 29, 2010 5:43 am
I'm sorry, I didn't post the OA. The OA says it is 200.

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by Night reader » Wed Dec 29, 2010 5:46 am
anuptvm wrote:Of the 800 employees in company X, 70 percent have been in the company for over 10 years. If y of these "long term" employees were to retire and no other employee changes were to occur, what value of y would reduce the percent of "long term" employees in the company to 60 percent?
[(800*70%) - y] / (800-y) = 60/100 => y=200
Last edited by Night reader on Wed Dec 29, 2010 5:47 am, edited 1 time in total.

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by Anurag@Gurome » Wed Dec 29, 2010 5:47 am
anuptvm wrote:Of the 800 employees in company X, 70 percent have been in the company for over 10 years. If y of these "long term" employees were to retire and no other employee changes were to occur, what value of y would reduce the percent of "long term" employees in the company to 60 percent?
Total number of employees = 800
Number of "long term" employees = 70% of 800 = 560

After y "long term" employees retire,
  • Total number of employees = (800 - y)
    Number of "long term" employees = 60% of 800 = 0.6*(800 - y)
Therefore, 0.6*(800 - y) = (560 - y)
=> (480 - 0.6y) = (560 - y)
=> 0.4y = 80
=> y = 200
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