GMAT Question of the Day - Daily to your Mailbox; hard ones only

 It is currently 15 Oct 2019, 15:06

### GMAT Club Daily Prep

#### Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

# At a certain hedge fund, there are only CFAs and MBAs. The average num

Author Message
TAGS:

### Hide Tags

Senior Manager
Joined: 25 Sep 2018
Posts: 423
Location: United States (CA)
Concentration: Finance, Strategy
GMAT 1: 640 Q47 V30
GPA: 3.97
WE: Investment Banking (Investment Banking)
At a certain hedge fund, there are only CFAs and MBAs. The average num  [#permalink]

### Show Tags

06 Oct 2018, 11:30
8
00:00

Difficulty:

45% (medium)

Question Stats:

67% (02:12) correct 33% (02:49) wrong based on 50 sessions

### HideShow timer Statistics

At a certain hedge fund, there are only CFAs and MBAs. The average number of vacation days taken by the CFAs is 5 fewer than the average number of vacation days taken per employee at the hedge fund. The average number of vacation days taken by the MBAs is 10 more than the average number of vacations days taken per employee at the hedge fund. What fraction of the hedge fund employees are CFAs?

A)$$\frac{1}{8}$$

B)$$\frac{1}{4}$$

C)$$\frac{1}{2}$$

D)$$\frac{2}{3}$$

E)$$\frac{3}{4}$$

_________________
Why do we fall?...So we can learn to pick ourselves up again
Math Expert
Joined: 02 Aug 2009
Posts: 7957
Re: At a certain hedge fund, there are only CFAs and MBAs. The average num  [#permalink]

### Show Tags

07 Oct 2018, 06:17
Abhi077 wrote:
At a certain hedge fund, there are only CFAs and MBAs. The average number of vacation days taken by the CFAs is 5 fewer than the average number of vacation days taken per employee at the hedge fund. The average number of vacation days taken by the MBAs is 10 more than the average number of vacations days taken per employee at the hedge fund. What fraction of the hedge fund employees are CFAs?

A)$$\frac{1}{8}$$

B)$$\frac{1}{4}$$

C)$$\frac{1}{2}$$

D)$$\frac{2}{3}$$

E)$$\frac{3}{4}$$

Use weighted average method ..
C... Average....M
x-5.....x.......x+10
So C/total = $$\frac{(x+10)-x}{x+10-(x-5)}$$=$$\frac{10}{15}=\frac{2}{3}$$
D

Or

Total number of leave by CFA= C*(x-5)
Total number of leave by MBA= M*(x+10)
Total number of leave = T*x
So T*x=Cx-5C+Mx+10M=(C+M)*X.......5C=10M....C=2M
Total =C+M=2M+M=3M
So C/T=2M/3M=2/3
D
_________________
Director
Joined: 19 Oct 2013
Posts: 519
Location: Kuwait
GPA: 3.2
WE: Engineering (Real Estate)
Re: At a certain hedge fund, there are only CFAs and MBAs. The average num  [#permalink]

### Show Tags

07 Oct 2018, 09:22
Abhi077 wrote:
At a certain hedge fund, there are only CFAs and MBAs. The average number of vacation days taken by the CFAs is 5 fewer than the average number of vacation days taken per employee at the hedge fund. The average number of vacation days taken by the MBAs is 10 more than the average number of vacations days taken per employee at the hedge fund. What fraction of the hedge fund employees are CFAs?

A)$$\frac{1}{8}$$

B)$$\frac{1}{4}$$

C)$$\frac{1}{2}$$

D)$$\frac{2}{3}$$

E)$$\frac{3}{4}$$

If we let X be the number of CFAs and Y the number of MBAs.

A be the sum of leaves taken by CFAs
B be the sum of leaves taken by MBAs

Let the average of leaves for all employees be z

We want to know x/(x+y)

We are given a/x = z - 5

a = x(z-5)

b/y = z + 10

b = y (z + 10)

Average of all = (a+b)/(x+y) = z

we get x = 2y

x/x+y = 2y/(2y+y) = 2/3 answer choice D

Posted from my mobile device
Intern
Joined: 09 Apr 2018
Posts: 31
GPA: 4
At a certain hedge fund, there are only CFAs and MBAs. The average num  [#permalink]

### Show Tags

15 Oct 2018, 22:47
1
This problem can be solved by treating it like a weighted average prooblem.

Let the average number of holidays/employee be x (the weighted average).
From the stem we know that the average number of holidays/CFA = x-5 and the average number of holidays/MBA = x+10.

Apppying the teeter totter method (from MGMAT): Thus, the the total distance between x-5 and x+10 = 15.

x-5--------------------x-----------------------x+10
distance from x=5 , distance from x=10

As we want to determine the number of CFAs, we can use the above teeter totter to conclude CFAs make up $$\frac{10}{15}=\frac{2}{3}$$of the total number of employees.

Using the teeter totter is a great way to simplify and visualise. Moreover, this approach is quite fast and took me around 1.5 minutes.

Please hit Kudos if you liked this approach
At a certain hedge fund, there are only CFAs and MBAs. The average num   [#permalink] 15 Oct 2018, 22:47
Display posts from previous: Sort by