At a certain company, the average (arithmetic mean) number : DS Archive
Check GMAT Club Decision Tracker for the Latest School Decision Releases http://gmatclub.com/AppTrack

 It is currently 19 Jan 2017, 13:20

### 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

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# At a certain company, the average (arithmetic mean) number

Author Message
CEO
Joined: 29 Mar 2007
Posts: 2583
Followers: 19

Kudos [?]: 421 [1] , given: 0

At a certain company, the average (arithmetic mean) number [#permalink]

### Show Tags

17 Oct 2007, 18:01
1
KUDOS
1
This post was
BOOKMARKED
00:00

Difficulty:

35% (medium)

Question Stats:

69% (01:15) correct 31% (00:24) wrong based on 109 sessions

### HideShow timer Statistics

This topic is locked. If you want to discuss this question please re-post it in the respective forum.

At a certain company, the average (arithmetic mean) number of years of experience is 9.8 years for the male employees and 9.1 years for the female employees. What is the ratio of the number of the company's male employees to the number of the company's female employees?

1) There are 52 male employees at the company.

2) The average number of years of experience for the company's male and female employees combined is 9.3 years.
[Reveal] Spoiler: OA
CEO
Joined: 29 Mar 2007
Posts: 2583
Followers: 19

Kudos [?]: 421 [2] , given: 0

Re: At a certain company, the average (arithmetic mean) number [#permalink]

### Show Tags

17 Oct 2007, 18:03
2
KUDOS
Is this a correct approach? (I posted OA below, just wanted to see if I got it correctly or just by accident) Thanks.

Let:
X=total yrs for males
Y=total yrs for females
M= males
F= females.

X/M=9.8
Y/F=9.1

(X+Y)/M+F=9.3

The average number of years of experience for the company's male and female employees combined is 9.3 years.

X=9.8M
Y=9.1F

(9.8M+9.1F)/M+F=9.3 ---> 9.8M+9.1F=9.3M+9.3F -->

.5M=.2F---> .5M/F=.2---> M/F=.2/.5 ---> M/F=2/5

From this I get B.
CEO
Joined: 21 Jan 2007
Posts: 2756
Location: New York City
Followers: 11

Kudos [?]: 854 [1] , given: 4

Re: At a certain company, the average (arithmetic mean) number [#permalink]

### Show Tags

21 Feb 2008, 07:45
1
KUDOS
GMATBLACKBELT wrote:
Big-O wrote:
Looks like the right approach... I did it without math.

(1) doesn't talk anything about # of years of experience - INSUFFICIENT

(2), the weighted average of 9.1 and 9.8 is 9.3 ... It allows for multiple values of 9.1 and 9.8 to make that 9.3 ... But the ratio will always be constant - SUFFICIENT

Can you explain this a bit more?? thx.

it's exactly what you did. its just terminology

weighted avg = (s1 +s2)/(N1+N2)

The combined sums are divided by the combined # of elements to produce a weighted outcome.
_________________

You tried your best and you failed miserably. The lesson is 'never try'. -Homer Simpson

Manager
Joined: 25 Aug 2007
Posts: 70
Schools: HBS '10
Followers: 1

Kudos [?]: 3 [0], given: 0

Re: At a certain company, the average (arithmetic mean) number [#permalink]

### Show Tags

17 Oct 2007, 18:08
Looks like the right approach... I did it without math.

(1) doesn't talk anything about # of years of experience - INSUFFICIENT

(2), the weighted average of 9.1 and 9.8 is 9.3 ... It allows for multiple values of 9.1 and 9.8 to make that 9.3 ... But the ratio will always be constant - SUFFICIENT
Director
Joined: 01 Jan 2008
Posts: 629
Followers: 4

Kudos [?]: 175 [0], given: 1

Re: At a certain company, the average (arithmetic mean) number [#permalink]

### Show Tags

21 Feb 2008, 08:39
GMATBLACKBELT wrote:
At a certain company, the average (arithmetic mean) number of years of experience is 9.8 years for the male employees and 9.1 years for the female employees. What is the ratio of the number of the company's male employees to the number of the company's female employees?

1) There are 52 male employees at the company.

2) The average number of years of experience for the company's male and female employees combined is 9.3 years.

B is the answer -> weighted average -> ratio of male to female is 2:5
GMAT Club Legend
Joined: 09 Sep 2013
Posts: 13456
Followers: 575

Kudos [?]: 163 [0], given: 0

Re: At a certain company, the average (arithmetic mean) number [#permalink]

### Show Tags

11 Nov 2015, 15:46
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________
Re: At a certain company, the average (arithmetic mean) number   [#permalink] 11 Nov 2015, 15:46
Display posts from previous: Sort by
{"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "url": "http://gmatclub.com/forum/at-a-certain-company-the-average-arithmetic-mean-number-54079.html?kudos=1", "fetch_time": 1484860843000000000, "content_mime_type": "text/html", "warc_filename": "crawl-data/CC-MAIN-2017-04/segments/1484560280746.40/warc/CC-MAIN-20170116095120-00077-ip-10-171-10-70.ec2.internal.warc.gz", "warc_record_offset": 116222548, "warc_record_length": 46023, "token_count": 1553, "char_count": 5347, "score": 4.0, "int_score": 4, "crawl": "CC-MAIN-2017-04", "snapshot_type": "latest", "language": "en", "language_score": 0.8908519744873047, "file_path": "/sailhome/yjruan/project/latent-lm/data/processed/finemath-4plus/finemath-4plus/train-00010-of-00064.parquet"}