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

It is currently 22 Aug 2018, 01:00

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

20 workmen can make 35 widgets in 5 days. How many workmen are needed

  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: 48119
20 workmen can make 35 widgets in 5 days. How many workmen are needed  [#permalink]

Show Tags

New post 07 Jul 2017, 01:58
1
00:00
A
B
C
D
E

Difficulty:

  5% (low)

Question Stats:

95% (00:41) correct 5% (00:56) wrong based on 154 sessions

HideShow timer Statistics

Manager
Manager
User avatar
S
Joined: 11 Jul 2016
Posts: 54
Location: India
Concentration: Technology, General Management
GMAT 1: 550 Q36 V30
GPA: 3.65
WE: Information Technology (Consulting)
Re: 20 workmen can make 35 widgets in 5 days. How many workmen are needed  [#permalink]

Show Tags

New post 07 Jul 2017, 02:15
1
35w--------5days------20Men
1w----------5days------20/35Men
1w----------1day---------(20/35)*5 Men
105w-------1day--------(20/35)*5*105Men
105w-------5days-------(20/35)*5*105*1/5 Men
Ans=60 Men
SVP
SVP
User avatar
P
Joined: 08 Jul 2010
Posts: 2139
Location: India
GMAT: INSIGHT
WE: Education (Education)
Reviews Badge
Re: 20 workmen can make 35 widgets in 5 days. How many workmen are needed  [#permalink]

Show Tags

New post 07 Jul 2017, 05:15
1
Bunuel wrote:
20 workmen can make 35 widgets in 5 days. How many workmen are needed to make 105 widgets in 5 days?

(A) 7
(B) 20
(C) 25
(D) 30
(E) 60



CONCEPT: \(\frac{(Machine_Power * Time)}{Work} = Constant\)
i.e. \(\frac{(M_1 * T_1)}{W_1} = \frac{(M_2 * T_2)}{W_2}\)

i.e. \(\frac{(20 * 5)}{35} = \frac{(M_2 * 5)}{105}\)

i.e. \(M_2 = 60\)

Answer: option E
_________________

Prosper!!!
GMATinsight
Bhoopendra Singh and Dr.Sushma Jha
e-mail: info@GMATinsight.com I Call us : +91-9999687183 / 9891333772
Online One-on-One Skype based classes and Classroom Coaching in South and West Delhi
http://www.GMATinsight.com/testimonials.html

22 ONLINE FREE (FULL LENGTH) GMAT CAT (PRACTICE TESTS) LINK COLLECTION

Director
Director
User avatar
D
Joined: 04 Dec 2015
Posts: 700
Location: India
Concentration: Technology, Strategy
Schools: ISB '19, IIMA , IIMB, XLRI
WE: Information Technology (Consulting)
GMAT ToolKit User
Re: 20 workmen can make 35 widgets in 5 days. How many workmen are needed  [#permalink]

Show Tags

New post 07 Jul 2017, 06:28
1
Bunuel wrote:
20 workmen can make 35 widgets in 5 days. How many workmen are needed to make 105 widgets in 5 days?

(A) 7
(B) 20
(C) 25
(D) 30
(E) 60


\(20\) workmen can make \(35\) widgets in \(5\) days.

Let the number of workmen to make \(105\) widgets in \(5\) days be \(= x\)

Number of days ie; \(5\) is same in both cases, hence we can ignore that.

\(\frac{20}{35} = \frac{x}{105}\)

\(x = \frac{20*105}{35} = 60\)

Hence \(60\) men are required to make \(105\) widgets in \(5\) days.

Answer (E)...
SC Moderator
avatar
V
Joined: 22 May 2016
Posts: 1916
Premium Member CAT Tests
20 workmen can make 35 widgets in 5 days. How many workmen are needed  [#permalink]

Show Tags

New post 07 Jul 2017, 07:27
1
Bunuel wrote:
20 workmen can make 35 widgets in 5 days. How many workmen are needed to make 105 widgets in 5 days?

(A) 7
(B) 20
(C) 25
(D) 30
(E) 60

W = # * r * t, where # = number of workers. Manipulate that equation in same way as W = rt.

Individual worker's rate is 35/(5*20), or 35/100, or \(\frac{7}{20}\)

New # of workers, using individual rate, is 105/[(7/20)*5], or 105/(35/20), or 105/(7/4) =

105 * \(\frac{4}{7}\) = 60

Answer E
_________________

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

-- Albert Camus, "Return to Tipasa"

VP
VP
avatar
P
Joined: 07 Dec 2014
Posts: 1069
20 workmen can make 35 widgets in 5 days. How many workmen are needed  [#permalink]

Show Tags

New post 07 Jul 2017, 11:17
Bunuel wrote:
20 workmen can make 35 widgets in 5 days. How many workmen are needed to make 105 widgets in 5 days?

(A) 7
(B) 20
(C) 25
(D) 30
(E) 60


let w=workmen needed
because time is equal,
w/20=105/35
w=60 workmen
E
SVP
SVP
User avatar
D
Joined: 26 Mar 2013
Posts: 1785
Reviews Badge CAT Tests
Re: 20 workmen can make 35 widgets in 5 days. How many workmen are needed  [#permalink]

Show Tags

New post 08 Jul 2017, 03:02
2
Bunuel wrote:
20 workmen can make 35 widgets in 5 days. How many workmen are needed to make 105 widgets in 5 days?

(A) 7
(B) 20
(C) 25
(D) 30
(E) 60



This problem could be solved conceptually without calculations

We have 20 worker to produce 35 widgtes in 5 days. In same number of days, we need more worker to produce Three TIMES (105/35 =3) the first situation. So we need 3 Times labor.

Answer: 60
Senior Manager
Senior Manager
User avatar
B
Joined: 28 Jun 2015
Posts: 295
Concentration: Finance
GPA: 3.5
Re: 20 workmen can make 35 widgets in 5 days. How many workmen are needed  [#permalink]

Show Tags

New post 08 Jul 2017, 03:52
The output has increased but not the number of days, so the number of men should increase linearly.

Since the output has become thrice, the number of men required will be = 20*3 = 60. Ans - E.
_________________

I used to think the brain was the most important organ. Then I thought, look what’s telling me that.

Manager
Manager
avatar
G
Joined: 04 Jan 2016
Posts: 166
Location: United States (NY)
GMAT 1: 620 Q44 V32
GMAT 2: 600 Q48 V25
GMAT 3: 660 Q42 V39
GPA: 3.48
GMAT ToolKit User Premium Member
20 workmen can make 35 widgets in 5 days. How many workmen are needed  [#permalink]

Show Tags

New post 08 Jul 2017, 20:24
First we can derive the rate of one workman as below:
\(20(R)*5=35 => R=\frac{7}{20}\)

Let X be the number of workmen needed and we have the work required (105) and the number of days worked (5) therefore,

\(\frac{X * 7}{20} * 5 = 105 => \frac{35X}{20} = 105 => 35 X = 105 * 20\) = > divide both sides by 35 => \(x = 3*20 = 60\)
Target Test Prep Representative
User avatar
G
Status: Head GMAT Instructor
Affiliations: Target Test Prep
Joined: 04 Mar 2011
Posts: 2781
Re: 20 workmen can make 35 widgets in 5 days. How many workmen are needed  [#permalink]

Show Tags

New post 12 Jul 2017, 16:30
1
Bunuel wrote:
20 workmen can make 35 widgets in 5 days. How many workmen are needed to make 105 widgets in 5 days?

(A) 7
(B) 20
(C) 25
(D) 30
(E) 60


We are given that the rate of 20 workmen is 35/5 = 7 widgets per day. We need to determine how many workmen are needed for a rate of 105/5 = 21 widgets per day. We can let x = the number of workman and create the following proportion:

20/7 = x/21

(20)(21) = 7x

(20)(3) = x

60 = x

Answer: E
_________________

Jeffery Miller
Head of GMAT Instruction

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

EMPOWERgmat Instructor
User avatar
V
Status: GMAT Assassin/Co-Founder
Affiliations: EMPOWERgmat
Joined: 19 Dec 2014
Posts: 12226
Location: United States (CA)
GMAT 1: 800 Q51 V49
GRE 1: Q170 V170
Re: 20 workmen can make 35 widgets in 5 days. How many workmen are needed  [#permalink]

Show Tags

New post 05 Dec 2017, 12:55
2
Hi All,

When dealing with these types of 'work' questions, it can be helpful to think in terms of the total amount of work that needs to be done to complete the given task. We're told that it takes 20 workmen 5 days to complete the task. That's...

(20 men)(5 days each) = 100 work-days of effort to create 35 widgets.

Thus, there are a number of different ways to complete that work:
1 worker can work for 100 days
2 workers can work for 50 days each
4 workers can work for 25 days each
Etc.

The question asks us to create 105 widgets, which is 3 times the 35 in the above calculation. Those 105 widgets would take 3(100) = 300 work-days of effort. If we have to complete the job in 5 days, then we can set up the following equation:

(X men)(5 days each) = 300 work-days

X = 60 men

Final Answer:

GMAT assassins aren't born, they're made,
Rich
_________________

760+: Learn What GMAT Assassins Do to Score at the Highest Levels
Contact Rich at: Rich.C@empowergmat.com

Rich Cohen

Co-Founder & GMAT Assassin

Special Offer: Save $75 + GMAT Club Tests Free
  Official GMAT Exam Packs + 70 Pt. Improvement Guarantee
www.empowergmat.com/

***********************Select EMPOWERgmat Courses now include ALL 6 Official GMAC CATs!***********************

Re: 20 workmen can make 35 widgets in 5 days. How many workmen are needed &nbs [#permalink] 05 Dec 2017, 12:55
Display posts from previous: Sort by

20 workmen can make 35 widgets in 5 days. How many workmen are needed

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

Events & Promotions

PREV
NEXT


cron

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®.