In company X, 70% of the male employees and 38% of the female employee

Question

In company X, 70% of the male employees and 38% of the female employees received a negative performance review. What fraction of company X’s employees are male?

1. 42% of company X employees received a negative performance review
2. Company X has a total of 440 employees

RenB · Answer

Did not know one can use the Alligation method here:
 
 Male/ Female Total Company avg Ratio in company 
Male (Higher %) 70 4 |38-42|
Company avg 42
Female (Lower %) 38 28 |70-42|

Ratio of men in total company = 4/(28+4)= 4/32= 1/8

mysterymanrog · Answer

Given:
0.7M got a bad review, and 0.38F got a bad review. 
The company is composed of M and F, in such a way that M+F=T (where T is the total)
We need to determine M/T

1) 
If 42% of the total employees got a bad review, this implies that:
0.42T=0.7M+0.38F
recall that T=M+F
0.42(M+F)=0.7M+0.38F
0.42M+0.42F=0.7M+0.38F
0.04F=0.28M
F=0.28M/0.04
Recall that we need to determine M/T (or M/(M+F)
Since we now have F in terms of M, it is entirely possible to sub F in terms of M in the above equation, and find the ratio of male employees. 
Sufficient.

2) 
Even if we know the total number of employees who got a bad review, this does not help us to find the ratio of male/total employees, since it depends on what percentage of the company got bad reviews. INS.

Choice must be A.

jaswanthxvasudev · Answer

Applying the Seesaw Method to Statement (1)

Draw a number line. Place the two group percentages on it, along with the overall average from Statement (1).
 
 Female Percentage (Negative Reviews):  38%  
 Male Percentage (Negative Reviews):  70%  
 Overall Average (The Fulcrum):  42%   
It looks like this:
 Females <----------------- Overall -----------------> Males

38% 42% 70% 
  Calculate the "Distance" of Each Group from the Overall Average 
 
 How far is the Female group from the average? 42−38=4 units. 
 How far is the Male group from the average? 70−42=28 units.  
 Find the Inverse Ratio of the Distances 
The ratio of the distances is 
 (Female Distance) : (Male Distance) 
 which is 4:28.
the ratio of the group  sizes  is the  INVERSE  of this.
So, the ratio of the number of people 
 (Number of Females) : (Number of Males) 
 is 28:4.
  Simplify and Answer the Question 
Simplify the ratio 28:4. Divide both sides by 4 to get 7:1.
This means 
 (Number of Females) : (Number of Males) = 7 : 1 
. For every 7 females, there is 1 male.
The question asks for the fraction of employees that are male (TM). In a representative group of 7+1=8 people, exactly 1 is male.
Hence sufficient. you can also do it using algebra.

DonBosco7 · Answer

From question stem and statement 1, you essentially get two equations as such:
(x = no. of male, y = no. of females, z = total employees)

0.7x + 0.38y = 0.42z
0.3x + 0.62y = 0.58z

solve the above two you'll get either y = some z OR x = some z .......... depending on which one you want to cancel out first.

from this we can then find out what is originally asked i.e/ x/z = ?

Hence only statement 1 is sufficient.
A

In company X, 70% of the male employees and 38% of the female employee

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GMAT Data Sufficiency (DS) Questions

In company X, 70% of the male employees and 38% of the female employee

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