It is currently 24 Sep 2017, 17:58

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

Events & Promotions in June
Open Detailed Calendar

At his regular hourly rate, Don had estimated the labour cos

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

Hide Tags

Expert Post
EMPOWERgmat Instructor
User avatar
P
Status: GMAT Assassin/Co-Founder
Affiliations: EMPOWERgmat
Joined: 19 Dec 2014
Posts: 9825

Kudos [?]: 3319 [0], given: 172

Location: United States (CA)
GMAT 1: 800 Q51 V49
GRE 1: 340 Q170 V170
Re: At his regular hourly rate, Don had estimated the labour cos [#permalink]

Show Tags

New post 08 Oct 2015, 10:27
Hi paidlukkha,

You can certainly treat this prompt as a 'system' question (2 variables and 2 unique equations.

Your first equation is correct:

336 = (X)(H)

However, your second equation is NOT. Since the number of hours increases by 4 and the difference in hourly pay is 2, the equation should be...

336 = (X - 2)(H + 4)

From here, you can proceed with the Algebra and you'll get to the solution.

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!***********************

Kudos [?]: 3319 [0], given: 172

Verbal Forum Moderator
Verbal Forum Moderator
User avatar
Joined: 29 Apr 2015
Posts: 895

Kudos [?]: 1722 [0], given: 302

Location: Switzerland
Concentration: Economics, Finance
Schools: LBS MIF '19
WE: Asset Management (Investment Banking)
GMAT ToolKit User Premium Member
Re: At his regular hourly rate, Don had estimated the labour cos [#permalink]

Show Tags

New post 22 Oct 2015, 12:44
So you have two equations from the question stem. Let x be the hourly rate and y the time in hours:

\(x*y=336\)

and

\((y+4)*(x-2) = 336\) which expands to: \(xy-2y+4x-8=336\)

plug in \(x*y=336\) in the above formula:

\(336-2y+4x-8=336\), simplify to:

\(2x-y-2=0\)

Now pick numbers which fit, start with C, then go up to B: 2x-24-4=0, if y=24, then x=14 and 2x=28. So this fits.
_________________

Saving was yesterday, heat up the gmatclub.forum's sentiment by spending KUDOS!

PS Please send me PM if I do not respond to your question within 24 hours.

Kudos [?]: 1722 [0], given: 302

Director
Director
User avatar
Joined: 10 Mar 2013
Posts: 595

Kudos [?]: 434 [0], given: 200

Location: Germany
Concentration: Finance, Entrepreneurship
GMAT 1: 580 Q46 V24
GPA: 3.88
WE: Information Technology (Consulting)
GMAT ToolKit User
Re: At his regular hourly rate, Don had estimated the labour cos [#permalink]

Show Tags

New post 10 Nov 2015, 15:29
BrainLab wrote:
t(t+4)=672
we can estimate here 20*30=600 --> 22*30=660 So we see that only A or B can be the answer here... 24*28 suits better (22*30)

A bit too large numbers to calculate, not really a GMAT Style, though it's an official GMAT Question.......


Update
We can complete a square here: \(t^2+4t=672\)-> \(t^2+4t+4=672+4\) --> \((t+2)^2=26^2\)
T=24, -28 Answer (B)
_________________

When you’re up, your friends know who you are. When you’re down, you know who your friends are.

Share some Kudos, if my posts help you. Thank you !

800Score ONLY QUANT CAT1 51, CAT2 50, CAT3 50
GMAT PREP 670
MGMAT CAT 630
KAPLAN CAT 660

Kudos [?]: 434 [0], given: 200

Intern
Intern
avatar
Joined: 18 Aug 2012
Posts: 10

Kudos [?]: 9 [0], given: 1

GMAT 1: 730 Q50 V39
At his regular hourly rate, Don had estimated the labour cos [#permalink]

Show Tags

New post 29 Nov 2015, 12:43
Given Info: The total hours estimated by Don differs from the actual number of hours required to finish the job. He had to work 4 more hours to finish the job. For this reason, he received $2 less than was estimated to be given per hour for his job. He received a total amount of $336 to complete his job.

Interpreting the Problem: We have to find the time Don had initially estimated to complete his job. This can be worked out by forming two equations from 2 different conditions given to us. One can be worked out on the number of hours initially estimated and his hourly rate to complete the job, and the other could be worked out on the actual hours worked nd actual hourly rate he received for the job. After that, we will equate both the equations to the total payment received and find the hours estimated for the job.

Solution:
Let us assume the time estimated by Don for the job be n hours and let the cost Don charges per hour for the job be $x per hour.

From the information in the question

n Hours (estimated) * x(Don charge for job per hour) = $336
Equation 1: \(nx=336\)

Also, from the information in the question

n+4(Hours actualltaken to complete the job)*x-2(Don actual payment per hour)=$336
Equation 2: \((n+4)(x-2)=336\)

Solving equations 1 and 2 for n and x
Putting nx from equation 1 in equation 2

\(336+4x-2n-8=336\)
\(4x-2n=8\)

Putting value of x in terms of n from Equation 1

\(4(336/n)-2n=8\)
\(672/n-n=4\)
\(n^2+4n-672=0\)
\(n^2+28n-24n-672=0\)
\((n+28)(n-24)=0\)
\(n=24\)(Ignoring n=-28 as number of hours cannot be negative)

So time Don had estimated to finish the job is 24 hours.
Hence, the Answer is B

Kudos [?]: 9 [0], given: 1

1 KUDOS received
Intern
Intern
avatar
Joined: 08 Feb 2016
Posts: 2

Kudos [?]: 6 [1], given: 28

Location: United States
GMAT 1: 700 Q46 V41
GPA: 3.61
WE: Brand Management (Health Care)
Re: At his regular hourly rate, Don had estimated the labour cos [#permalink]

Show Tags

New post 25 Feb 2016, 20:06
1
This post received
KUDOS
Reverse Plug in!

1) Start with the middle number and determine in you should go up or down:
336/16= $21/hr 16 is choice C
Next add 4 hours -> 336/20 = 16.8. hour
Difference is not 2. Move up in hours

2) 336/24 = 14 24 is choice B
Next add 4 hours -> 336/28=12
Difference is 2 so this is the answer

Kudos [?]: 6 [1], given: 28

BSchool Forum Moderator
User avatar
P
Joined: 12 Aug 2015
Posts: 2219

Kudos [?]: 806 [0], given: 595

GMAT ToolKit User Premium Member CAT Tests
Re: At his regular hourly rate, Don had estimated the labour cos [#permalink]

Show Tags

New post 09 Mar 2016, 21:39
Hey Anyone Looking for a more algebraic approach?
here is what i actually did
let it took x hours to complete the Job
So wage per hour = 336/x

now as per question => it took x+4 hours to do the job and he was paid => 336/x - 2 /hour
now total wage must remain constant
hence 336 = (336/x - 2 ) * (x+4)
=> x^2 +8x - 672 = 0
x=-8+52/2 (neglecting the negative value as hours are non negative )
x= 28

Hence A is sufficient ...

Would Love your Thoughts on this approach .. MathRevolution
_________________

Give me a hell yeah ...!!!!!

Kudos [?]: 806 [0], given: 595

Senior Manager
Senior Manager
User avatar
S
Status: Professional GMAT Tutor
Affiliations: AB, cum laude, Harvard University (Class of '02)
Joined: 10 Jul 2015
Posts: 394

Kudos [?]: 460 [0], given: 53

Location: United States (CA)
Age: 37
GMAT 1: 770 Q47 V48
GMAT 2: 730 Q44 V47
GMAT 3: 750 Q50 V42
GRE 1: 337 Q168 V169
WE: Education (Education)
At his regular hourly rate, Don had estimated the labour cos [#permalink]

Show Tags

New post 26 May 2016, 17:33
This is one of the toughest questions in the OG: 85% incorrect on GMAT Club!

I have found that this one is much easier if you just draw a factor tree and use a little bit of trial and error with the various factors (and combinations thereof). Look for one set of numbers that is 4 apart, and the other 2 apart, and you have your answer.

You know that the rate and the time are going to be relatively close to one another, because a difference of $2 in Don's hourly rate results in a difference of 4 hours in the time spent on the job. These numbers are not exactly the same, but they are close, suggesting that r and t are relatively close to one another in value.

Attached is a visual that should help.
Attachments

Screen Shot 2016-05-26 at 5.33.02 PM.png
Screen Shot 2016-05-26 at 5.33.02 PM.png [ 108.82 KiB | Viewed 1023 times ]


_________________

Harvard grad and 770 GMAT scorer, offering high-quality private GMAT tutoring, both in-person and via Skype, since 2002.

McElroy Tutoring

Kudos [?]: 460 [0], given: 53

Senior Manager
Senior Manager
User avatar
Joined: 18 Jan 2010
Posts: 258

Kudos [?]: 135 [0], given: 9

Re: At his regular hourly rate, Don had estimated the labour cos [#permalink]

Show Tags

New post 27 May 2016, 02:47
Suppose Don estimated that the job will be completed in t hours.

Then his hourly rate becomes \(\frac{336}{t}\) $ per hour.

Now when works for 4 hours longer, his hourly rate is $2 less.
so

\(\frac{336}{t+4}\) will be the hourly rate

\(\frac{336}{t}\) - 2 = \(\frac{336}{t+4}\)

t(t+4) = 2 *21*16 = 24 * 28

We get t = 24

Answer is B

Kudos [?]: 135 [0], given: 9

Director
Director
avatar
G
Joined: 07 Dec 2014
Posts: 803

Kudos [?]: 226 [0], given: 10

At his regular hourly rate, Don had estimated the labour cos [#permalink]

Show Tags

New post 27 May 2016, 14:35
algebraic approach with one variable
336/t*(t+4)-2(t+4)=336
t^2+4t-672=0
t=24 hours

Kudos [?]: 226 [0], given: 10

Expert Post
Target Test Prep Representative
User avatar
S
Status: Founder & CEO
Affiliations: Target Test Prep
Joined: 14 Oct 2015
Posts: 1537

Kudos [?]: 779 [0], given: 2

Location: United States (CA)
Re: At his regular hourly rate, Don had estimated the labour cos [#permalink]

Show Tags

New post 16 Jun 2016, 06:02
macjas wrote:
At his regular hourly rate, Don had estimated the labour cost of a repair job as $336 and he was paid that amount. However, the job took 4 hours longer than he had estimated and, consequently, he earned $2 per hour less than his regular hourly rate. What was the time Don had estimated for the job, in hours?

(A) 28
(B) 24
(C) 16
(D) 14
(E) 12


To solve this problem we can translate the problem with the given information into an equation. Since we don’t know Don's hourly rate nor the time he had estimated for the job, we use two variables:

w = Don’s hourly rate

t = number of hours he estimated for the job

We are given that Don was paid $336, based on his original estimate, so we can say:

w x t = 336

Next we are given that the job took 4 hours longer and that, as a result, he earned 2 dollars less than his regular rate. This leads us to say:

(w – 2)(t + 4) = 336

We rewrite the equation w x t = 336 as w = 336/t. Now we substitute 336/t for w in the equation (w – 2)(t + 4) = 336. Thus, we have:

[(336/t) – 2](t + 4) = 336

After FOILing we have:

336 + (4x336)/t – 2t – 8 = 336

(4x336)/t – 2t – 8 = 0

Multiplying the entire equation by t, we get:

4 x 336 – 2t^2 – 8t = 0

Dividing the entire equation by 2, we get:

2 x 336 – t^2 – 4t = 0 or 672 – t^2 – 4t = 0

We can also rewrite this as: t^2 + 4t – 672 = 0

Now this is where we should be strategic with our answer choices. To solve this quadratic we are looking for two numbers that sum to a positive 4 and multiply to a negative 672. Our answer choices are:

(A) 28
(B) 24
(C) 16
(D) 14
(E) 12

There are only two pairs of answer choices that are 4 units apart: 16 and 12, and 28 and 24. Since 24 multiplied by 28 is 672, we know that the numbers that are needed for the factoring are 24 and 28. Thus, we can say:

(t – 24)(t + 28) = 0

We can see that t = 24 or t = -28. However, since we can’t have a negative number of hours, only t = 24 is the correct answer.

Answer B
_________________

Scott Woodbury-Stewart
Founder and CEO

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

Kudos [?]: 779 [0], given: 2

Manager
Manager
avatar
Joined: 28 Jun 2016
Posts: 207

Kudos [?]: 79 [0], given: 63

Location: Canada
Concentration: Operations, Entrepreneurship
Re: At his regular hourly rate, Don had estimated the labour cost [#permalink]

Show Tags

New post 29 Oct 2016, 17:06
336/(t+4) = 336/t -2

(336+2t+8)*t = 336t +1344

2t^2+8t-1344=0

t^2+4t-672=0

(t+28)(t-24)=0

t = 24 or -28

Time cannot be negative.

So t=24.




Sent from my iPhone using GMAT Club Forum mobile app

Kudos [?]: 79 [0], given: 63

Manager
Manager
avatar
S
Joined: 13 Mar 2013
Posts: 179

Kudos [?]: 74 [0], given: 25

Location: United States
Concentration: Leadership, Technology
GPA: 3.5
WE: Engineering (Telecommunications)
Re: At his regular hourly rate, Don had estimated the labour cos [#permalink]

Show Tags

New post 10 May 2017, 23:11
Hi Bunuel ,

Could you please explain , where it given in the question that
w – 2)(t + 4) = 336

Regards
_________________

Regards ,

Kudos [?]: 74 [0], given: 25

Expert Post
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 41699

Kudos [?]: 124810 [0], given: 12079

At his regular hourly rate, Don had estimated the labour cos [#permalink]

Show Tags

New post 11 May 2017, 02:48
abhisheknandy08 wrote:
Hi Bunuel ,

Could you please explain , where it given in the question that
w – 2)(t + 4) = 336

Regards


Say the regular hourly rate was \(r\)$ and estimated time was \(t\) hours.

We are told that the job took 4 hours longer than he had estimated and, consequently, he earned $2 per hour less than his regular hourly rate, thus \((r-2)(t+4)=336\).

Complete solution is here: https://gmatclub.com/forum/at-his-regul ... l#p1109300
_________________

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

Kudos [?]: 124810 [0], given: 12079

Senior Manager
Senior Manager
User avatar
G
Joined: 13 Mar 2017
Posts: 458

Kudos [?]: 94 [0], given: 53

Location: India
Concentration: General Management, Entrepreneurship
GPA: 3.8
WE: Engineering (Energy and Utilities)
At his regular hourly rate, Don had estimated the labour cos [#permalink]

Show Tags

New post 11 May 2017, 03:31
macjas wrote:
At his regular hourly rate, Don had estimated the labour cost of a repair job as $336 and he was paid that amount. However, the job took 4 hours longer than he had estimated and, consequently, he earned $2 per hour less than his regular hourly rate. What was the time Don had estimated for the job, in hours?

(A) 28
(B) 24
(C) 16
(D) 14
(E) 12

Let the regular hourly rate of Don is x.
And the estimated time is y.
-> xy =336

Since he took 4 hours longer than the estimated time & was paid the $2 per hour less than his regular hourly rate.
(x-2)(y+4) = 336
-> xy - 2y + 4x - 8 = 336
-> 336 + 4x - 2y - 8 = 336
-> 4x -2y = 8
-> 2x - y = 4
-> 2x - 336/x = 4
-> x - 168/x = 2
-> x^2 - 168 - 2x = 0
-> x^2 - 14x + 12x - 168 = 0
-> x(x-14) + 12(x-14) = 0
-> (x+12)(x-14) = 0
-> x = 14

Estimated time y = 336/14 = 24.

[Reveal] Spoiler:
Answer.... B

_________________

MBA Social Network : WebMaggu

Appreciate by Clicking +1 Kudos ( Lets be more generous friends.)

Kudos [?]: 94 [0], given: 53

VP
VP
User avatar
D
Status: Long way to go!
Joined: 10 Oct 2016
Posts: 1035

Kudos [?]: 646 [0], given: 49

Location: Viet Nam
GMAT ToolKit User Premium Member CAT Tests
Re: At his regular hourly rate, Don had estimated the labour cos [#permalink]

Show Tags

New post 11 May 2017, 08:37
macjas wrote:
At his regular hourly rate, Don had estimated the labour cost of a repair job as $336 and he was paid that amount. However, the job took 4 hours longer than he had estimated and, consequently, he earned $2 per hour less than his regular hourly rate. What was the time Don had estimated for the job, in hours?

(A) 28
(B) 24
(C) 16
(D) 14
(E) 12


\(x\) is the hours that Don had estimated, so \(\frac{336}{x}\) is the money per hour he earned.

We have \((x+4)\times (\frac{336}{x}-2)=336\)
\(\implies (x+4)(336-2x)=336x \\
\implies 336x - 2x^2 + 4\times 336 - 8x = 336x \\
\implies 2x^2 +8x = 4 \times 336 \\
\implies x^2 +4x = 2\times 336 = 672 \\
\implies x^2 + 4x + 4 = 676 \\
\implies (x+2)^2 = 676\)

Note that \(676 = 2\times 338 =2 \times 2 \times 169 = 2^2 \times 13^2 = 26^2\)
Hence \((x+2)^2=26^2 \implies x+2=26\) since \(x > 0\)

\(\implies x=24\). The answer is B.
_________________

Actual LSAT CR bank by Broall

How to solve quadratic equations - Factor quadratic equations
Factor table with sign: The useful tool to solve polynomial inequalities
Applying AM-GM inequality into finding extreme/absolute value

New Error Log with Timer

Kudos [?]: 646 [0], given: 49

Intern
Intern
avatar
Joined: 20 May 2017
Posts: 4

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

At his regular hourly rate, Don had estimated the labour cos [#permalink]

Show Tags

New post 22 May 2017, 13:30
Hi guys,

I have two questions:

1) I understand every part of the solution, but I need a lot of time for factoring (last step):

(t^2)+4t-672=0 --> factor
(t-24)(t+28)=0

How do you do that? What is your approach?
What I would do is, split 672 up into its factors, which are 2^5*3*7 ... and then I try every single calculation to find the right figures.

2) How can questions like this be done within 2 minutes?
Even after I knew this question by heart, it took me 5 1/2 minutes to get it done, by writing all the important steps down, without taking a break to think.
There are worse questions than this one, but still ...

Thanks,
Tom

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

Intern
Intern
avatar
B
Joined: 18 May 2017
Posts: 19

Kudos [?]: 0 [0], given: 113

WE: Corporate Finance (Health Care)
GMAT ToolKit User
Re: At his regular hourly rate, Don had estimated the labour cos [#permalink]

Show Tags

New post 07 Jun 2017, 18:30
Bunuel wrote:
macjas wrote:
At his regular hourly rate, Don had estimated the labour cost of a repair job as $336 and he was paid that amount. However, the job took 4 hours longer than he had estimated and, consequently, he earned $2 per hour less than his regular hourly rate. What was the time Don had estimated for the job, in hours?

(A) 28
(B) 24
(C) 16
(D) 14
(E) 12


Say the regular hourly rate was \(r\)$ and estimated time was \(t\) hours, then we would have:

\(rt=336\) and \((r-2)(t+4)=336\);

So, \((r-2)(t+4)=rt\) --> \(rt+4r-2t-8=rt\) --> \(t=2r-4\).

Now, plug answer choices for \(t\) and get \(r\). The pair which will give the product of 336 will be the correct answer.

Answer B fits: if \(t=24\) then \(r=14\) --> \(rt=14*24=336\).

Answer: B.

Hope it's clear.




I am still a confused . Could you please show how you arrived at T=2R-4 ?

Kudos [?]: 0 [0], given: 113

VP
VP
avatar
S
Joined: 09 Jun 2010
Posts: 1411

Kudos [?]: 153 [0], given: 916

Re: At his regular hourly rate, Don had estimated the labour cos [#permalink]

Show Tags

New post 08 Jun 2017, 03:34
BrainLab wrote:
BrainLab wrote:
t(t+4)=672
we can estimate here 20*30=600 --> 22*30=660 So we see that only A or B can be the answer here... 24*28 suits better (22*30)

A bit too large numbers to calculate, not really a GMAT Style, though it's an official GMAT Question.......


Update
We can complete a square here: \(t^2+4t=672\)-> \(t^2+4t+4=672+4\) --> \((t+2)^2=26^2\)
T=24, -28 Answer (B)



pick the answer choices are most easy for this problem .
_________________

visit my facebook to help me.
on facebook, my name is: thang thang thang

Kudos [?]: 153 [0], given: 916

Top Contributor
SVP
SVP
User avatar
G
Joined: 12 Sep 2015
Posts: 1755

Kudos [?]: 2302 [0], given: 355

Location: Canada
At his regular hourly rate, Don had estimated the labour cos [#permalink]

Show Tags

New post 28 Aug 2017, 14:26
Top Contributor
macjas wrote:
At his regular hourly rate, Don had estimated the labour cost of a repair job as $336 and he was paid that amount. However, the job took 4 hours longer than he had estimated and, consequently, he earned $2 per hour less than his regular hourly rate. What was the time Don had estimated for the job, in hours?

(A) 28
(B) 24
(C) 16
(D) 14
(E) 12


Here's an algebraic solution:

Let h = # of hours that Don ESTIMATED for the job.
So, h + 4 = ACTUAL # of hours it took Don to complete the job.

So, IF Don, had completed the job in h hours, his RATE would have = $336/h
However, since Don completed the job in h+4 hours, his RATE was actually = $336/(h + 4)

...consequently, he earned 2$ per hour less than his regular hourly rate.
In other words, (John's estimated rate) - 2 = (John's actual rate)
So, $336/h - 2 = $336/(h + 4)

ASIDE: since the above equation is a bit of a pain to solve, you might consider plugging in the answer choices to see which one works.

Okay, let's solve this: $336/h - 2 = $336/(h + 4)
To eliminate the fractions, multiply both sides by (h)(h+4) to get: 336(h+4) - 2(h)(h+4) = 336h
Expand: 336h + 1344 - 2h² - 8h = 336h
Simplify: -2h² - 8h + 1344 = 0
Multiply both sides by -1 to get: 2h² + 8h - 1344 = 0
Divide both sides by 2 to get: h² + 4h - 672 = 0
Factor (yeeesh!) to get: (h - 24)(h + 28) = 0
Solve to get: h = 24 or h = -28
Since h cannot be negative (in the real world), h must equal 24.

Answer:
[Reveal] Spoiler:
B

_________________

Brent Hanneson – Founder of gmatprepnow.com

Image

Kudos [?]: 2302 [0], given: 355

Manager
Manager
User avatar
B
Joined: 07 Jun 2017
Posts: 56

Kudos [?]: 9 [0], given: 28

Location: India
Concentration: Technology, General Management
GPA: 3.6
WE: Information Technology (Computer Software)
GMAT ToolKit User
Re: At his regular hourly rate, Don had estimated the labour cos [#permalink]

Show Tags

New post 01 Sep 2017, 00:29
Plug the Answer choice always take from middle (C)
here 336/16 = 21, so 19*20 not equal to 336 and also it is 380 so go lesser value
(B)
336 /24 = 14, S0 12* 26 = 336 fits so answer is
B
_________________

Regards,
Naveen
email: nkmungila@gmail.com

Kudos [?]: 9 [0], given: 28

Re: At his regular hourly rate, Don had estimated the labour cos   [#permalink] 01 Sep 2017, 00:29

Go to page   Previous    1   2   [ 40 posts ] 

Display posts from previous: Sort by

At his regular hourly rate, Don had estimated the labour cos

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


GMAT Club MBA Forum Home| About| Terms and Conditions| 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®.