A company has only two types of employees - clerks and managers. The a

Question

A company has only two types of employees - clerks and managers. The average salary of the clerks is $40,000 and the average salary of the managers is $120,000. If the average salary of all employees in the company is $45,000 and there are 30 managers in the company, what is the number of clerks in the company?

(A) 2
(B) 20
(C) 45
(D) 200
(E) 450

Show Answer

Official Answer

E

(A) 2
(B) 20
(C) 45
(D) 200
(E) 450

sujoykrdatta · Accepted Answer

Clerks get $40 and managers get $120
Average is $45

Deviation from mean for each manager = (+)$75
For 30 managers, total positive deviation = 30 * 75 = 2250

Deviation from mean for clerks = (-)$5

Since sum of deviations about mean MUST be ZERO, we have:

Total negative deviation for clerks = -2250
Thus, number of clerks = (-2250)/(-5) = 450

Answer E

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Alternatively, you may form an equation assuming x clerks and solve for x (the longer way)

Camcam1 · Answer

Clerks get 40 and Managers 120
There is 30 managers
x is the number of Clerks in the company

Use the average method: 
(30*120+x*40)/(30+x) = 45

3600+40x = 1350 + 45x
x=2250/5 
x= 450

Hence answer E

EgmatQuantExpert · Answer

Given  
 • A company has only two types of employees - clerks and managers.
• Average salary of the clerks = $40,000
• Average salary of the Manager = $120,000
• Average salary of all employees in the company = $45,000
• Total managers in the company = 30
 
  To find
  
 • Number of clerks in the company

Approach  
Let number of clerks in the company = n
 • Total Salary of Managers + Total salary of clerks = Total salary paid to all employees
• 30 × $120,000 + n × $40,000 = (30 + n) × $45,000
• 30 × 24 + n × 8 = (30 + n) × 9
• n = 30 × 15 
• n = 450

Hence, the correct answer is  option E.

CrackverbalGMAT · Answer

Use the rule of alligations as shown below.

Let x be the number of clerks

Therefore  \frac{x}{75000} = \frac{30}{5000}

x = 450

Option E

Arun Kumar

deepfuknchange · Answer

How long did this take you? I solved this way and took just under 3 min

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