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

It is currently 17 Jul 2018, 12:38

Close

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
Your Progress

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

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Close

Request Expert Reply

Confirm Cancel

At a technology firm, employees are categorizes as either engineers or

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

Expert Post
2 KUDOS received
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 47037
At a technology firm, employees are categorizes as either engineers or [#permalink]

Show Tags

New post 29 Aug 2017, 23:44
2
3
00:00
A
B
C
D
E

Difficulty:

  25% (medium)

Question Stats:

80% (02:04) correct 20% (02:06) wrong based on 81 sessions

HideShow timer Statistics

At a technology firm, employees are categorizes as either engineers or non-engineers. 80% of the engineers have a masters degree and 55% of the non-engineers have a masters degree. If 70% of all employees have a masters degree, what percent of all employees are engineers?

A. 55%
B. 60%
C. 65%
D. 70%
E. 75%

_________________

New to the Math Forum?
Please read this: Ultimate GMAT Quantitative Megathread | All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics

Most Helpful Expert Reply
Expert Post
4 KUDOS received
Target Test Prep Representative
User avatar
G
Status: Head GMAT Instructor
Affiliations: Target Test Prep
Joined: 04 Mar 2011
Posts: 2669
Re: At a technology firm, employees are categorizes as either engineers or [#permalink]

Show Tags

New post 02 Sep 2017, 07:11
4
1
Bunuel wrote:
At a technology firm, employees are categorizes as either engineers or non-engineers. 80% of the engineers have a masters degree and 55% of the non-engineers have a masters degree. If 70% of all employees have a masters degree, what percent of all employees are engineers?

A. 55%
B. 60%
C. 65%
D. 70%
E. 75%


We can let the total employees = 100.

Thus, 70 have a master’s degree and 30 do not.

We can let n = the number of engineers and create the following equation:

0.8n + 0.55(100 - n) = 70

0.8n + 55 - 0.55n = 70

0.25n = 15

n = 60

Thus, engineers are 60% of the employees.

Answer: B
_________________

Jeffery Miller
Head of GMAT Instruction

GMAT Quant Self-Study Course
500+ lessons 3000+ practice problems 800+ HD solutions

Most Helpful Community Reply
4 KUDOS received
Director
Director
User avatar
P
Joined: 18 Aug 2016
Posts: 631
Concentration: Strategy, Technology
GMAT 1: 630 Q47 V29
GMAT 2: 740 Q51 V38
GMAT ToolKit User Premium Member Reviews Badge
At a technology firm, employees are categorizes as either engineers or [#permalink]

Show Tags

New post Updated on: 30 Aug 2017, 01:07
4
1
Bunuel wrote:
At a technology firm, employees are categorizes as either engineers or non-engineers. 80% of the engineers have a masters degree and 55% of the non-engineers have a masters degree. If 70% of all employees have a masters degree, what percent of all employees are engineers?

A. 55%
B. 60%
C. 65%
D. 70%
E. 75%

...................M..............NM..............Total
E...............0.8x............0.2x...............x
NE............0.55y...........0.45y..............y
Total.....0.8x+0.55y....0.2x+0.45y.......x+y

\(0.8x+0.55y = 0.7(x+y)\)
\(0.1x = 0.15y\)
\(x=1.5y\)
Since we have to calculate the % of engineers from all employees..eqn would be x/(x+y)
\(1.5y/(1.5y+y)\)
1.5/2.5 = 60%
B
_________________

We must try to achieve the best within us


Thanks
Luckisnoexcuse


Originally posted by Luckisnoexcuse on 30 Aug 2017, 00:28.
Last edited by Luckisnoexcuse on 30 Aug 2017, 01:07, edited 1 time in total.
General Discussion
Manager
Manager
User avatar
S
Status: Searching for something I've been searching..LOL
Joined: 14 Dec 2016
Posts: 63
Location: India
Concentration: Healthcare, Operations
Schools: Ross '20
GMAT 1: 590 Q35 V42
GPA: 3.5
WE: Medicine and Health (Health Care)
GMAT ToolKit User
Re: At a technology firm, employees are categorizes as either engineers or [#permalink]

Show Tags

New post 30 Aug 2017, 01:01
Luckisnoexcuse wrote:
Bunuel wrote:
At a technology firm, employees are categorizes as either engineers or non-engineers. 80% of the engineers have a masters degree and 55% of the non-engineers have a masters degree. If 70% of all employees have a masters degree, what percent of all employees are engineers?

A. 55%
B. 60%
C. 65%
D. 70%
E. 75%

M NM Total
E 0.8x 0.2x x
NE 0.55y 0.45y y
Total 0.8x+0.55y 0.2x+0.45y x+y

0.8x+0.55y = 0.7(x+y)
0.1x = 0.15y
x=1.5y
1.5/2.5 = 60%
B



Would you be kind enough to explain how you got the denominator in the highlighted step??? Luckisnoexcuse
Director
Director
User avatar
P
Joined: 18 Aug 2016
Posts: 631
Concentration: Strategy, Technology
GMAT 1: 630 Q47 V29
GMAT 2: 740 Q51 V38
GMAT ToolKit User Premium Member Reviews Badge
At a technology firm, employees are categorizes as either engineers or [#permalink]

Show Tags

New post 30 Aug 2017, 01:04
kill3rlook5 wrote:
Luckisnoexcuse wrote:
Bunuel wrote:
At a technology firm, employees are categorizes as either engineers or non-engineers. 80% of the engineers have a masters degree and 55% of the non-engineers have a masters degree. If 70% of all employees have a masters degree, what percent of all employees are engineers?

A. 55%
B. 60%
C. 65%
D. 70%
E. 75%

M NM Total
E 0.8x 0.2x x
NE 0.55y 0.45y y
Total 0.8x+0.55y 0.2x+0.45y x+y

0.8x+0.55y = 0.7(x+y)
0.1x = 0.15y
x=1.5y
1.5/2.5 = 60%
B



Would you be kind enough to explain how you got the denominator in the highlighted step??? Luckisnoexcuse

Sure kill3rlook5
We have to calculate x/(x+y) since x = 1.5y
x/(x+y) = 1.5y/(1.5y + y) = 1.5/2.5..which is 60% in % terms
Hope it helps
_________________

We must try to achieve the best within us


Thanks
Luckisnoexcuse

Manager
Manager
User avatar
S
Status: Searching for something I've been searching..LOL
Joined: 14 Dec 2016
Posts: 63
Location: India
Concentration: Healthcare, Operations
Schools: Ross '20
GMAT 1: 590 Q35 V42
GPA: 3.5
WE: Medicine and Health (Health Care)
GMAT ToolKit User
Re: At a technology firm, employees are categorizes as either engineers or [#permalink]

Show Tags

New post 30 Aug 2017, 01:18
Quote:
Sure kill3rlook5
We have to calculate x/(x+y) since x = 1.5y
x/(x+y) = 1.5y/(1.5y + y) = 1.5/2.5..which is 60% in % terms
Hope it helps



Thanks a ton for explaining that. I was on the verge of tearing my hair trying to understand that.... :-D :-D :-D :-D
SC Moderator
avatar
D
Joined: 22 May 2016
Posts: 1826
Premium Member CAT Tests
At a technology firm, employees are categorizes as either engineers or [#permalink]

Show Tags

New post 30 Aug 2017, 18:01
Luckisnoexcuse wrote:
Bunuel wrote:
At a technology firm, employees are categorizes as either engineers or non-engineers. 80% of the engineers have a masters degree and 55% of the non-engineers have a masters degree. If 70% of all employees have a masters degree, what percent of all employees are engineers?

A. 55%
B. 60%
C. 65%
D. 70%
E. 75%

...................M..............NM..............Total
E...............0.8x............0.2x...............x
NE............0.55y...........0.45y..............y
Total.....0.8x+0.55y....0.2x+0.45y.......x+y

\(0.8x+0.55y = 0.7(x+y)\)
\(0.1x = 0.15y\)
\(x=1.5y\)
Since we have to calculate the % of engineers from all employees..eqn would be x/(x+y)
\(1.5y/(1.5y+y)\)
1.5/2.5 = 60%
B

I used your equation, but not your chart, and confused myself for a LONG time about total, despite the fact that I had just used both variables in a weighted average to find the ratio of x to y.

I kept thinking that I had failed to account for the other 30 percent who were not included in the equation. I chose B, unconvinced.

Then I saw your post. I'm still not sure I understand what happened to the other 30 percent, but I believe you.

Nice work. And kudos.
_________________

In the depths of winter, I finally learned
that within me there lay an invincible summer.

-- Albert Camus, "Return to Tipasa"

Manager
Manager
avatar
B
Joined: 04 May 2014
Posts: 162
Location: India
WE: Sales (Mutual Funds and Brokerage)
Re: At a technology firm, employees are categorizes as either engineers or [#permalink]

Show Tags

New post 10 Sep 2017, 21:04
Overlapping sets problem. we can use 2X2 table.
Attachments

Screen Shot 2017-09-11 at 9.33.11 AM.png
Screen Shot 2017-09-11 at 9.33.11 AM.png [ 34.29 KiB | Viewed 833 times ]

1 KUDOS received
Senior Manager
Senior Manager
User avatar
S
Status: love the club...
Joined: 24 Mar 2015
Posts: 278
Re: At a technology firm, employees are categorizes as either engineers or [#permalink]

Show Tags

New post 10 Sep 2017, 22:14
1
Bunuel wrote:
At a technology firm, employees are categorizes as either engineers or non-engineers. 80% of the engineers have a masters degree and 55% of the non-engineers have a masters degree. If 70% of all employees have a masters degree, what percent of all employees are engineers?

A. 55%
B. 60%
C. 65%
D. 70%
E. 75%




70 = .8x + (100 - x)* .55
solving for x we can get the answer ...

hope this helps
cheers ..
CR Forum Moderator
User avatar
P
Status: He came. He saw. He conquered. -- Studying for the LSAT
Joined: 31 Jul 2017
Posts: 266
Location: United States
Concentration: Finance, Economics
Reviews Badge
At a technology firm, employees are categorizes as either engineers or [#permalink]

Show Tags

New post 11 Sep 2017, 11:57
Explaining the photo below using the see-saw method:

Please forgive the crudeness of the drawing!

The ratio of masters degrees is 3:2 (15:10), weighted towards engineers. So, engineers comprise 60% of the company. We get this because we know 55% of non engineers have their degree, and 80% of engineers do as well, so you can determine the weight of each, given that 70% of the total company have their degree.

Notice the tilt towards the engineer side, so you don't get confused with the 15 and 10.
Attachments

picture 1.png
picture 1.png [ 13.12 KiB | Viewed 747 times ]


_________________

D-Day: November 18th, 2017

Need a laugh and a break? Go here: https://gmatclub.com/forum/mental-break-funny-videos-270269.html

At a technology firm, employees are categorizes as either engineers or   [#permalink] 11 Sep 2017, 11:57
Display posts from previous: Sort by

At a technology firm, employees are categorizes as either engineers or

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  

Events & Promotions

PREV
NEXT


GMAT Club MBA Forum Home| About| Terms and Conditions and Privacy Policy| GMAT Club Rules| Contact| Sitemap

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne

Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.