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

It is currently 09 Dec 2018, 11:40

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
Events & Promotions in December
PrevNext
SuMoTuWeThFrSa
2526272829301
2345678
9101112131415
16171819202122
23242526272829
303112345
Open Detailed Calendar
  • Free GMAT Algebra Webinar

     December 09, 2018

     December 09, 2018

     07:00 AM PST

     09:00 AM PST

    Attend this Free Algebra Webinar and learn how to master Inequalities and Absolute Value problems on GMAT.
  • Free lesson on number properties

     December 10, 2018

     December 10, 2018

     10:00 PM PST

     11:00 PM PST

    Practice the one most important Quant section - Integer properties, and rapidly improve your skills.

x identical machines can make x widgets in x minutes. If each machine

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

Hide Tags

Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 51035
x identical machines can make x widgets in x minutes. If each machine  [#permalink]

Show Tags

New post 24 Apr 2017, 03:25
1
11
00:00
A
B
C
D
E

Difficulty:

  35% (medium)

Question Stats:

68% (01:29) correct 32% (01:36) wrong based on 175 sessions

HideShow timer Statistics

x identical machines can make x widgets in x minutes. If each machine works at the same constant rate, how many widgets can y identical machines make in y minutes, in terms of x and y?

A. x
B. y
C. y^2
D. x/y
E. y^2/x

_________________

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

VP
VP
User avatar
P
Joined: 05 Mar 2015
Posts: 1004
x identical machines can make x widgets in x minutes. If each machine  [#permalink]

Show Tags

New post 24 Apr 2017, 10:31
1
x machine-------x minutes---------x widgets

x machine-------1 minutes---------x /x widgets(=1 widget)

1 machine-------1 minutes---------1/x widgets (rate of x machine)

similarly
let Y machine in y minutes make A widget. then

y machine-------y minutes---------A widgets

y machine-------1 minutes---------A/y widgets

1 machine-------1 minutes---------A/y^2 widgets (rate of y machine)

As rates are equal

A/y^2 = 1/x
A =y^2/x

Ans E
Intern
Intern
avatar
S
Joined: 28 Oct 2014
Posts: 34
Location: India
Concentration: General Management, Operations
Schools: ISB '19 (A)
GMAT 1: 680 Q50 V30
GPA: 3.89
WE: Engineering (Aerospace and Defense)
GMAT ToolKit User
x identical machines can make x widgets in x minutes. If each machine  [#permalink]

Show Tags

New post 24 Apr 2017, 10:57
1
Number of Widgets is directly proportional to Number of machines and Time taken.

So we can write it as \(W ∝T*N\) ==> \(W=K*T*N\)

Where
W= Number of Widgets
T= Time Taken
N= Number of Machine
K= Equation constant (Don't Worry about this :wink:)

From the given Problem

\(x=K*x*x\)

On Solving above equation \(K=\frac{1}{x}\)

\(Wy= K*y*y\)

on substituting \(K=\frac{1}{x}\) ==> \(Wy=\frac{y^2}{x}\)


Kudos +1
Target Test Prep Representative
User avatar
G
Status: Head GMAT Instructor
Affiliations: Target Test Prep
Joined: 04 Mar 2011
Posts: 2830
Re: x identical machines can make x widgets in x minutes. If each machine  [#permalink]

Show Tags

New post 27 Apr 2017, 16:11
1
1
1
Bunuel wrote:
x identical machines can make x widgets in x minutes. If each machine works at the same constant rate, how many widgets can y identical machines make in y minutes, in terms of x and y?

A. x
B. y
C. y^2
D. x/y
E. y^2/x


We are given that x identical machines can make x widgets in x minutes. Thus, the rate for the x machines is x/x or 1 widget per minute. Next we can determine the rate of y machines using the following proportion in which n is the rate for y machines:

x/1 = y/n

n = y/x

Since the rate for y machines is y/x and work = rate x time, y machines can produce (y/x)(y) = y^2/x widgets in y minutes.

Answer: E
_________________

Jeffery Miller
Head of GMAT Instruction

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

Manager
Manager
avatar
B
Joined: 14 May 2015
Posts: 51
Re: x identical machines can make x widgets in x minutes. If each machine  [#permalink]

Show Tags

New post 02 May 2017, 14:29
1
x identical machines.......working x minutes......can make= x widgets

1 identical machines.......working 1 minutes......can make[less] = x/(x+x) widgets

y identical machines.......working y minutes......can make[more] = (x/(x+x))*(y*y) widgets
= y^2 /x widgets

Answer: E
Intern
Intern
avatar
B
Joined: 23 Aug 2017
Posts: 26
x identical machines can make x widgets in x minutes. If each machine  [#permalink]

Show Tags

New post 03 Aug 2018, 10:54
Lets say that R is the rate and W the number of widgets

\(X * R = \frac{X}{X}\)
\(R = \frac{1}{X}\)

(Replacing R)
\(Y * R = \frac{W}{Y}\)
\(Y * \frac{1}{X} = \frac{W}{Y}\)
\(\frac{Y}{X} = \frac{W}{Y}\)
\(W = \frac{Y²}{X}\)

Option E
Senior SC Moderator
avatar
V
Joined: 22 May 2016
Posts: 2196
Premium Member CAT Tests
x identical machines can make x widgets in x minutes. If each machine  [#permalink]

Show Tags

New post 03 Aug 2018, 16:21
Bunuel wrote:
x identical machines can make x widgets in x minutes. If each machine works at the same constant rate, how many widgets can y identical machines make in y minutes, in terms of x and y?

A. x
B. y
C. y^2
D. x/y
E. y^2/x

Find the individual machine rate from scenario #1 (defined by \(x\)), then use that rate to find the number of widgets in scenario #2.

Scenario 1: x identical machines make x widgets in x minutes
(# of workers) * R * T = W
Plug in variables*
\(x*R*x=x\)
\(Rate=\frac{x}{x^2}\)

At that rate . . .
Scenario 2: y identical machines in y minutes can make how many widgets? (= Work)
(# of workers) * R * T = W
\(y*\frac{x}{x^2}*y=W\)
\(W=\frac{y*x*y}{x2}\)
\(W=\frac{y^2}{x}\)

Answer E

*In other words, manipulate the equation exactly as RT=W is manipulated with one more variable (# of machines) on LHS. Scenario #1:
\(R=\frac{W}{(No.Of.Machines*T)}\)
Scenario #2:
\(Work=(No.Of.Machines*R*T)\)
GMAT Club Bot
x identical machines can make x widgets in x minutes. If each machine &nbs [#permalink] 03 Aug 2018, 16:21
Display posts from previous: Sort by

x identical machines can make x widgets in x minutes. If each machine

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


Copyright

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®.