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At a certain university, all employees can be categorized as either pr
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18 May 2017, 00:18
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46% (02:09) correct 54% (02:02) wrong based on 138 sessions
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Re: At a certain university, all employees can be categorized as either pr
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18 May 2017, 11:35
Bunuel wrote: At a certain university, all employees can be categorized as either professors or administrators, and the average professor earns $18,000 more than the average administrator. How much less does the average administrator earn than the average employee at the university?
(1) The average salary of a professor is $88,000.
(2) There are twice as many administrators as professors. Analyzing question stem  Let there be "x" professors & "y" administrators. Also let the average salary of administrator be "a" So average salary of professor = a+18,000 This implies average salary of ALL the employees will be = {(a+18,000)*x+a*y} / (x+y)____[i.e. total salary of all employees upon total number of employees] As the question asks us to find out the difference between administrator's average salary and average salary of all employees = {(a+18,000)*x+a*y}/(x+y)  a = (ax+ay+18000x  ax+ay) / (x+y) Or, 18000x / (x+y) (Eq.1) So we only need relation between number of professors and number of administrators. Statement 1: Provides no info about number of profs & number of admin. Hence Insufficient Statement 2: Directly provides the relation between no. of profs. & no. of admin. Hence sufficient. (you can substitute the value in eq.1 to get the exact value but for DS it is not required) Hence Option B



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Re: At a certain university, all employees can be categorized as either pr
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19 May 2017, 14:11
Let:
Average Salary of an Administrator = $A Average Salary of an Professor = $A + 18000
Number of Administrators = M Number of Professors = N
Average Salary of all Employees (Administrators + Professors)
= [MA + N(A+1800)]/(M+N)
How much less does the average administrator earn than the average employee at the university
= [MA + N(A+1800)]/(M+N)  A
= (MA + NA + 18000N  MA  NA)/(M+N)
= (18000N)/(M+N)
To Solve this we would need
Number of Administrator and Professors
Statement 1:The average salary of a professor is $88,000.
This statement does not give the information we need. Hence is insufficient.
Statement 2:There are twice as many administrators as professors.
This means => M = 2N
Substituting in the above equation
= (18000N)/(M+N) = 18000N/(2N+N) = 18000N/3N = 6000
This statement is sufficient.
Answer is B



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Re: At a certain university, all employees can be categorized as either pr
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19 May 2017, 22:58
Statement 1. Average salary of a professor is 88000, that of administrator becomes 8800018000 = 70000. Let number of Administrators be A, number of professors be P.
Average salary per employee = (70000*A + 880000*P)/(A+P) This cant be found unless we either know the values of A & P or the ratio A:P. So Insufficient.
Statement 2. Ratio of Administrators (A) and Professors (P) is 2:1. Let A = 2s, P = 1s. Let Average salary of an administrator be x, that of professor becomes (x+18000).
Net average salary per employee = [x*2s + (x+18000)*1s]/[2s+1s] = x+6000. While average salary per Administrator = x Their difference = x + 6000  x = 6000. So Sufficient.
Hence answer should be B



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Re: At a certain university, all employees can be categorized as either pr
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20 May 2017, 04:58
Bunuel wrote: At a certain university, all employees can be categorized as either professors or administrators, and the average professor earns $18,000 more than the average administrator. How much less does the average administrator earn than the average employee at the university?
(1) The average salary of a professor is $88,000.
(2) There are twice as many administrators as professors. Administrator average pay = $x Professor's average pay = $(x+18000) Question: AVerage of employee pay  x = ?P.S. To answer the question we need average of all employees and to calculate avergae of all employees we need ration of number of Administrators to the number of ProfessorsStatement 1: The average salary of a professor is $88,000.NOT SUFFICIENT Statement 2: There are twice as many administrators as professors.We get the ratio of Administrators to the Professors SUFFICIENT Answer: option B
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Re: At a certain university, all employees can be categorized as either pr
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10 Aug 2017, 02:54
Bunuel wrote: At a certain university, all employees can be categorized as either professors or administrators, and the average professor earns $18,000 more than the average administrator. How much less does the average administrator earn than the average employee at the university?
(1) The average salary of a professor is $88,000.
(2) There are twice as many administrators as professors. Given : All employees can be categorized as either professors or administrators P = A +18000 Let P,A,E be the avergae salaries of Professors, Administrators and Employees. DS: E  A = ? Statement 1 : P = 88000 A = 70000 But we don't know the numbers of professors and administrators. So we can't find the avergae salary of the total number of employees. NOT SUFFICIENTStatement 2 : Let p, a , e be the number of professors, administrators and employees. So, e = a + p also a = 2p Now average salary of employees E = (a*A + p*(A+18000))/(a+p) = (2p*A + p*(A+18000) )/(2p+p) = (3A + 18000)/ 3 = A+ 6000 So E A = 6000 SUFFICIENT Answer B
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Re: At a certain university, all employees can be categorized as either pr
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22 Sep 2018, 12:31
Quote: The "distance" between the average professor and administrator salary ($18,000) A question asking you specifically for the "distance" from the administrator salary to the weighted average. If you were to map this using the weighted average mapping strategy, you'd start with something like: AdminAverageProf
 (a distance of 18,000) Quote: Statement 1, looking at it this way, defines both the Professor salary ($88,000) and, therefore, the Administrator salary ($18,000 less than that, so $70,000). But it does not provide you with enough information to determine that weighted average, so statement 1 is not sufficient. Quote: Statement 2 alone, however, can be applied to solve for that weighted average. You're told that the ratio of Administrators to Professors is 2:1, meaning that the distance from Administrator to Average must be half as far as Average to Professor. Applying that ratio, you can see that the distances must be 6,000 and 12,000: AdminAverageProf
6,00012,000 And remember what they're asking: how much less does an administrator make than the average? This means that administrators are $6,000 less, so statement 2 is sufficient.




Re: At a certain university, all employees can be categorized as either pr &nbs
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