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

It is currently 14 Dec 2019, 12:01

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

Working simultaneously at an identical constant rate, it takes 6 machi

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

Hide Tags

Find Similar Topics 
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 59725
Working simultaneously at an identical constant rate, it takes 6 machi  [#permalink]

Show Tags

New post 29 Aug 2017, 23:41
00:00
A
B
C
D
E

Difficulty:

  15% (low)

Question Stats:

80% (01:24) correct 20% (01:52) wrong based on 138 sessions

HideShow timer Statistics

Manager
Manager
User avatar
S
Joined: 22 Aug 2016
Posts: 80
Location: India
Concentration: Operations, Finance
GMAT 1: 650 Q49 V29
GMAT 2: 710 Q49 V37
GPA: 3.5
WE: Other (Education)
Reviews Badge
Working simultaneously at an identical constant rate, it takes 6 machi  [#permalink]

Show Tags

New post 30 Aug 2017, 00:28
Bunuel wrote:
Working simultaneously at an identical constant rate, it takes 6 machines 8 hours to produce y widgets. How many machines, working at that identical constant rate, are necessary to produce 2y widgets in 4 hours?

A. 6
B. 12
C. 18
D. 24
E. 48


6 Machines -----8 Hours-----y widgets
So
6 Machines------4 Hours-----\(\frac{y}{2}\)widgets

But we need to produce 2y widgets in 4 hours.

To produce \(\frac{y}{2}\) widgets, we need 6 machines

So to produce 4*\(\frac{y}{2}\)widgets =2y widgets, we need 4*6 machines = 24 machines.

(D)
Manager
Manager
User avatar
S
Status: Searching for something I've been searching..LOL
Joined: 14 Dec 2016
Posts: 55
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: Working simultaneously at an identical constant rate, it takes 6 machi  [#permalink]

Show Tags

New post 30 Aug 2017, 00:31
1
Bunuel wrote:
Working simultaneously at an identical constant rate, it takes 6 machines 8 hours to produce y widgets. How many machines, working at that identical constant rate, are necessary to produce 2y widgets in 4 hours?

A. 6
B. 12
C. 18
D. 24
E. 48


6 machines working for 8 hrs produce y widgets
? machines working for 4 hrs to produce 2y widgets

Multiplication factor for time is New/Old = 4/8
Multiplication factor for widgets is New/Old = 2y/y

No of machines is directly proportional to Number of widgets needed to be made and inversely proportional to the time allotted for the work.

Hence Number of new machines will be 6*(8/4)*(2y/y) = 24

Hence answer should be D. 24

Kudos help someone feel appreciated and cost nothing. Do hit the Kudos if you feel this helped.
Current Student
User avatar
P
Joined: 18 Aug 2016
Posts: 593
Concentration: Strategy, Technology
GMAT 1: 630 Q47 V29
GMAT 2: 740 Q51 V38
GMAT ToolKit User Reviews Badge
Re: Working simultaneously at an identical constant rate, it takes 6 machi  [#permalink]

Show Tags

New post 30 Aug 2017, 00:32
1
Bunuel wrote:
Working simultaneously at an identical constant rate, it takes 6 machines 8 hours to produce y widgets. How many machines, working at that identical constant rate, are necessary to produce 2y widgets in 4 hours?

A. 6
B. 12
C. 18
D. 24
E. 48


6 m + 8 h = Y w
12 m + 8 h = 2Y w
24 m + 4 h = 2Y w

D
_________________
We must try to achieve the best within us


Thanks
Luckisnoexcuse
Senior SC Moderator
avatar
V
Joined: 22 May 2016
Posts: 3747
Working simultaneously at an identical constant rate, it takes 6 machi  [#permalink]

Show Tags

New post 30 Aug 2017, 16:49
Bunuel wrote:
Working simultaneously at an identical constant rate, it takes 6 machines 8 hours to produce y widgets. How many machines, working at that identical constant rate, are necessary to produce 2y widgets in 4 hours?

A. 6
B. 12
C. 18
D. 24
E. 48

# of machines(M) * rate * time = Work

The individual machine rate for 6 machines to produce y widgets in 8 hours is

\(\frac{y}{(6*8)}\) = \(\frac{y}{48}\)

To produce 2y widgets in 4 hours, working at that rate, it will take how many machines, M?

M * \(\frac{y}{48} * 4 = 2y\)

M = \(\frac{2y}{(\frac{4y}{48})}\), or

M = \(2y *
\frac{48}{4y}\) = 24 machines

Answer D
_________________
SC Butler has resumed! Get two SC questions to practice, whose links you can find by date, here.

Never doubt that a small group of thoughtful, committed citizens can change the world; indeed, it's the only thing that ever has -- Margaret Mead
Target Test Prep Representative
User avatar
G
Status: Head GMAT Instructor
Affiliations: Target Test Prep
Joined: 04 Mar 2011
Posts: 2809
Re: Working simultaneously at an identical constant rate, it takes 6 machi  [#permalink]

Show Tags

New post 02 Sep 2017, 07:17
1
Bunuel wrote:
Working simultaneously at an identical constant rate, it takes 6 machines 8 hours to produce y widgets. How many machines, working at that identical constant rate, are necessary to produce 2y widgets in 4 hours?

A. 6
B. 12
C. 18
D. 24
E. 48


We are given that the rate of 6 machines is y/8. Using a proportion, we can determine how many machines work at a rate of 2y/4 = y/2.

6/(y/8) = n/(y/2)

48/y = 2n/y

48y = 2ny

24 = n

Alternate solution:

We see that the number of widgets needed to be produced (2y) is twice the given number of widgets (y). Thus, we need to double 6 machines to 12 machines so that in 8 hours they can produce 2y widgets. However, we see we need to produce these 2y widgets in 4 hours, which is half of the given 8 hours. Thus, we need to double the machines again from 12 machines to 24 machines to produce 2y widgets in 4 hours.

Answer: D
_________________

Jeffrey Miller

Head of GMAT Instruction

Jeff@TargetTestPrep.com
TTP - Target Test Prep Logo
122 Reviews

5-star rated online GMAT quant
self study course

See why Target Test Prep is the top rated GMAT quant course on GMAT Club. Read Our Reviews

If you find one of my posts helpful, please take a moment to click on the "Kudos" button.

Intern
Intern
avatar
B
Joined: 31 Aug 2017
Posts: 7
Working simultaneously at an identical constant rate, it takes 6 machi  [#permalink]

Show Tags

New post 06 Sep 2017, 00:39
Bunuel wrote:
Working simultaneously at an identical constant rate, it takes 6 machines 8 hours to produce y widgets. How many machines, working at that identical constant rate, are necessary to produce 2y widgets in 4 hours?

A. 6
B. 12
C. 18
D. 24
E. 48


Let y = 24
Rates * Time = Work
(1/2*6) * 8 = 24=> (1/2*6) * 4 =12=> (1/2*x) *4 =48

1/2X * 4 =48
=>X = 24

Answer D
Director
Director
User avatar
D
Affiliations: IIT Dhanbad
Joined: 13 Mar 2017
Posts: 730
Location: India
Concentration: General Management, Entrepreneurship
GPA: 3.8
WE: Engineering (Energy and Utilities)
Re: Working simultaneously at an identical constant rate, it takes 6 machi  [#permalink]

Show Tags

New post 06 Sep 2017, 04:01
2
2
Bunuel wrote:
Working simultaneously at an identical constant rate, it takes 6 machines 8 hours to produce y widgets. How many machines, working at that identical constant rate, are necessary to produce 2y widgets in 4 hours?

A. 6
B. 12
C. 18
D. 24
E. 48


To produce y widget 6*8 = 48 Machine - hours are required
To produce 2y widget 48*2 = 96 Machine - hours are required
To produce 2y widget in 4 hours, 96/4 = 24 Machines are required. .... Answer D
Current Student
User avatar
B
Joined: 06 Sep 2016
Posts: 125
Location: Italy
Schools: EDHEC (A$)
GMAT 1: 650 Q43 V37
GPA: 3.2
WE: General Management (Human Resources)
Re: Working simultaneously at an identical constant rate, it takes 6 machi  [#permalink]

Show Tags

New post 06 Sep 2017, 08:19
JeffTargetTestPrep wrote:
Bunuel wrote:
Working simultaneously at an identical constant rate, it takes 6 machines 8 hours to produce y widgets. How many machines, working at that identical constant rate, are necessary to produce 2y widgets in 4 hours?

A. 6
B. 12
C. 18
D. 24
E. 48


We are given that the rate of 6 machines is y/8. Using a proportion, we can determine how many machines work at a rate of 2y/4 = y/2.

6/(y/8) = n/(y/2)

48/y = 2n/y

48y = 2ny

24 = n

Alternate solution:

We see that the number of widgets needed to be produced (2y) is twice the given number of widgets (y). Thus, we need to double 6 machines to 12 machines so that in 8 hours they can produce 2y widgets. However, we see we need to produce these 2y widgets in 4 hours, which is half of the given 8 hours. Thus, we need to double the machines again from 12 machines to 24 machines to produce 2y widgets in 4 hours.

Answer: D


Loved this tecnique! Kudos for you!
Manager
Manager
User avatar
B
Joined: 19 Jul 2017
Posts: 82
Location: India
Concentration: General Management, Strategy
GPA: 3.5
Re: Working simultaneously at an identical constant rate, it takes 6 machi  [#permalink]

Show Tags

New post 06 Sep 2017, 21:20
1
[quote="Bunuel"]Working simultaneously at an identical constant rate, it takes 6 machines 8 hours to produce y widgets. How many machines, working at that identical constant rate, are necessary to produce 2y widgets in 4 hours?

A. 6
B. 12
C. 18
D. 24
E. 48[/quote

6*R*8= y;
Given same rate so N*R*4=2y;
N*R*4= 2*6*R*8
N=96/4= 24

Ans:D
Manager
Manager
avatar
B
Joined: 17 Jul 2016
Posts: 54
Re: Working simultaneously at an identical constant rate, it takes 6 machi  [#permalink]

Show Tags

New post 23 Mar 2019, 21:05
it takes 6 machines 8 hours to produce y widgets.

It would take twice the number of machines (12) to produce 2y widgets in 8 hours.

To finish the job in half the time we need twice as many machines. 12x2=24 machines.
GMAT Club Bot
Re: Working simultaneously at an identical constant rate, it takes 6 machi   [#permalink] 23 Mar 2019, 21:05
Display posts from previous: Sort by

Working simultaneously at an identical constant rate, it takes 6 machi

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





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