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A company has 15 managers and 75 associates. The 15 managers have an [#permalink]
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24 Feb 2015, 07:41
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A company has 15 managers and 75 associates. The 15 managers have an average salary of $120,000. The 75 associates have an average salary of $30,000. What is the average salary for the company? A. $35,000 B. $45,000 C. $55,000 D. $65,000 E. $75,000 Kudos for a correct solution.
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Re: A company has 15 managers and 75 associates. The 15 managers have an [#permalink]
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24 Feb 2015, 09:35
Bunuel wrote: A company has 15 managers and 75 associates. The 15 managers have an average salary of $120,000. The 75 associates have an average salary of $30,000. What is the average salary for the company?
A. $35,000 B. $45,000 C. $55,000 D. $65,000 E. $75,000
Kudos for a correct solution. these questions can be done in two ways .. 1) average formula: (15*120000+75*30000)/(15+75)=45000 2) weighted average and ratio method: the two numbers are in ratio 15:75=1:5.... so the difference of average will be in ratio 5:1.. difference in avg salaries of two groups=12000030000=90000... now the average will be closer to higher number,75 , by 1/6 of 90000 =90000*1/6=15000.. so avg = 30000+15000=45000
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Re: A company has 15 managers and 75 associates. The 15 managers have an [#permalink]
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24 Feb 2015, 10:07
Another method is to get ratios Say 30000=a and We know the # of people are in 1:5 ratio Average=(4a*1+a*5)/6= 9a/6=1.5 a=45000
Answer is B. $45,000



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Re: A company has 15 managers and 75 associates. The 15 managers have an [#permalink]
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24 Feb 2015, 10:55
I solved this using average formula :
(15*120,000 + 75 * 30,000) / 90
= 45, 000
Answer B
However, with this approach I needed around 2 minutes. Is there a faster way?



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Re: A company has 15 managers and 75 associates. The 15 managers have an [#permalink]
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24 Feb 2015, 13:52
Well, the answer is obviously B , BUT in order to solve the question faster and calculate easier let's try this approach : AS you know some countries some times eliminate zeros in their currency because of high inflation in their countries , so we can apply this approach in order to solve the problem in a faster way lets eliminate 3 zero's from the big numbers , so we have 120 $ instead of 120,000 $ and also 30$ instead of 30,000$ we are told that company has 15 managers with average salary of 120$ .... so total amount of salary will be 15*120= 1800$ Also, we are told that the company has 75 associates with average salary of 30$ .... so total amount of salary for those guys will be 30*75= 2250$ Final stage : for calculating the total average salary we have the sum of two groups of people divided by the total number of people : ( 1800+2250) / (75+15) = 4050/90 OR : we can cancel out zero from denominator and numerator , so we have : 405/9 = 45 !!!!! by viewing to the answers ONLY option B fits ..... Took less than One minute.... Best Regards,



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Re: A company has 15 managers and 75 associates. The 15 managers have an [#permalink]
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24 Feb 2015, 20:18
Answer = B = 45000 Average salary \(= \frac{15*120000 + 75*30000}{15+75} = \frac{15*120000}{90} + \frac{75*30000}{90} = 20000 + 25000 = 45000\)
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Re: A company has 15 managers and 75 associates. The 15 managers have an [#permalink]
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24 Feb 2015, 23:31
mehrdadtaheri92 wrote: Well, the answer is obviously B , BUT in order to solve the question faster and calculate easier let's try this approach : AS you know some countries some times eliminate zeros in their currency because of high inflation in their countries , so we can apply this approach in order to solve the problem in a faster way lets eliminate 3 zero's from the big numbers , so we have 120 $ instead of 120,000 $ and also 30$ instead of 30,000$ we are told that company has 15 managers with average salary of 120$ .... so total amount of salary will be 15*120= 1800$ Also, we are told that the company has 75 associates with average salary of 30$ .... so total amount of salary for those guys will be 30*75= 2250$ Final stage : for calculating the total average salary we have the sum of two groups of people divided by the total number of people : ( 1800+2250) / (75+15) = 4050/90 OR : we can cancel out zero from denominator and numerator , so we have : 405/9 = 45 !!!!! by viewing to the answers ONLY option B fits ..... Took less than One minute.... Best Regards, Hi mehrdadtaheri92, I like your thinking  that's a clever way to eliminate some of the "excess math" and make the calculations easier. To that end, what would have happened if you had eliminated ALL of the 0s... and used 12 and 3 (instead of 120 and 30)? GMAT assassins aren't born, they're made, Rich
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Re: A company has 15 managers and 75 associates. The 15 managers have an [#permalink]
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28 Feb 2015, 07:36
Bunuel wrote: A company has 15 managers and 75 associates. The 15 managers have an average salary of $120,000. The 75 associates have an average salary of $30,000. What is the average salary for the company?
A. $35,000 B. $45,000 C. $55,000 D. $65,000 E. $75,000
Kudos for a correct solution. Let us ignore the last 3 zeros since they're common for all terms. Total salary of 15 managers = 15 * 120 = 1800 Total salary of 75 associates = 75 * 30 = 2250 Total salary of company = 1800 + 2250 = 4050 Average salary of 90 employees = 4050/90 = 45 Let us put back the 3 zeros again = 45000 Hence option B.  Optimus Prep's GMAT On Demand course for only $299 covers all verbal and quant. concepts in detail. Visit the following link to get your 7 days free trial account: http://www.optimusprep.com/gmatondemandcourse



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Re: A company has 15 managers and 75 associates. The 15 managers have an [#permalink]
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02 Mar 2015, 06:33
Bunuel wrote: A company has 15 managers and 75 associates. The 15 managers have an average salary of $120,000. The 75 associates have an average salary of $30,000. What is the average salary for the company?
A. $35,000 B. $45,000 C. $55,000 D. $65,000 E. $75,000
Kudos for a correct solution. MAGOOSH OFFICIAL SOLUTION:The 15 managers have an average salary of $120,000. The sum of their salaries is: sum = (average)*(number of salaries) = $120,000*15 = $1,800,000 The 75 associates have an average salary of $30,000. The sum of their salaries is: sum = (average)*(number of salaries) = $30,000*75 = $2,250,000 When we add those two sums, we get the total payroll of all 90 employees. $1,800,000 + $2,250,000 = $4,050,000 So, we have 90 employees, and together they earn $4,050,000, so the average is average = $4,050,000 ÷90 = $45,000 Answer: B.
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A company has 15 managers and 75 associates. The 15 managers have an [#permalink]
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02 Mar 2015, 14:28
EMPOWERgmatRichC wrote: mehrdadtaheri92 wrote: Well, the answer is obviously B , BUT in order to solve the question faster and calculate easier let's try this approach : AS you know some countries some times eliminate zeros in their currency because of high inflation in their countries , so we can apply this approach in order to solve the problem in a faster way lets eliminate 3 zero's from the big numbers , so we have 120 $ instead of 120,000 $ and also 30$ instead of 30,000$ we are told that company has 15 managers with average salary of 120$ .... so total amount of salary will be 15*120= 1800$ Also, we are told that the company has 75 associates with average salary of 30$ .... so total amount of salary for those guys will be 30*75= 2250$ Final stage : for calculating the total average salary we have the sum of two groups of people divided by the total number of people : ( 1800+2250) / (75+15) = 4050/90 OR : we can cancel out zero from denominator and numerator , so we have : 405/9 = 45 !!!!! by viewing to the answers ONLY option B fits ..... Took less than One minute.... Best Regards, Hi mehrdadtaheri92, I like your thinking  that's a clever way to eliminate some of the "excess math" and make the calculations easier. To that end, what would have happened if you had eliminated ALL of the 0s... and used 12 and 3 (instead of 120 and 30)? GMAT assassins aren't born, they're made, Rich Dear Friend, You are right of course , But dear friend Notice that eliminating 3 zeros can bring us simplicity enough to solve question fast. So, I over looked to eliminate zero.... But , you are right my friend, Thanks...



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Re: A company has 15 managers and 75 associates. The 15 managers have an [#permalink]
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07 Mar 2015, 10:47
LaxAvenger wrote: I solved this using average formula :
(15*120,000 + 75 * 30,000) / 90
= 45, 000
Answer B
However, with this approach I needed around 2 minutes. Is there a faster way? hi LaxAvenger , Check out the below link. It might help. http://www.veritasprep.com/blog/2011/03 ... averages/Thanks!



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Re: A company has 15 managers and 75 associates. The 15 managers have an [#permalink]
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