Find all School-related info fast with the new School-Specific MBA Forum

It is currently 13 Feb 2016, 07:49
GMAT Club Tests

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.

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

A store currently charges the same price for each towel that

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
Intern
Intern
avatar
Joined: 29 Mar 2011
Posts: 20
Followers: 0

Kudos [?]: 3 [0], given: 0

Re: PS numbers [#permalink] New post 08 May 2011, 11:52
Assuming n towels are bought and price of each towel is x.
n.x=120
price increase x+1
total towels that can be bought = n-10
now (n-10)(x+1)=120

Solving 2 equations --> x=(n-10)/10
Substituting answers, only x=3 solves the problem

Answer C
Director
Director
avatar
Joined: 01 Feb 2011
Posts: 758
Followers: 14

Kudos [?]: 86 [0], given: 42

Re: PS numbers [#permalink] New post 08 May 2011, 13:21
i agree with @beyongmat.. about the typo in question. there has to be a comma after 1.

=> \(120 = ((120/x)-10)(x+1)\)

=> x =3

Answer is C.
VP
VP
avatar
Status: There is always something new !!
Affiliations: PMI,QAI Global,eXampleCG
Joined: 08 May 2009
Posts: 1354
Followers: 15

Kudos [?]: 192 [0], given: 10

Re: PS numbers [#permalink] New post 08 May 2011, 19:36
let price for each towel = x

then 120/x = number of towels purchased.

(120/x) -10 = (120/(x+1)

substituting x = 3, LHS = RHS = 30 .

Hence C.
_________________

Visit -- http://www.sustainable-sphere.com/
Promote Green Business,Sustainable Living and Green Earth !!

SVP
SVP
avatar
Joined: 16 Nov 2010
Posts: 1675
Location: United States (IN)
Concentration: Strategy, Technology
Followers: 32

Kudos [?]: 413 [0], given: 36

Top 10 in overall Reviews Badge
Re: PS numbers [#permalink] New post 11 May 2011, 04:09
n*p = (n - 10)(p+1)


np = 120

120 = (120/p - 10) (p+1)

120p = (120 - 10p)(p+1)

12p = (12-p)(p+1)

Checking the values, p = 3

Answer - C
_________________

Formula of Life -> Achievement/Potential = k * Happiness (where k is a constant)

GMAT Club Premium Membership - big benefits and savings

Manager
Manager
avatar
Joined: 12 May 2011
Posts: 98
Location: United States
Concentration: Finance, Marketing
GMAT 1: 730 Q47 V44
GMAT 2: Q V
Followers: 1

Kudos [?]: 15 [0], given: 4

Re: 600-700 level question [#permalink] New post 04 Oct 2011, 20:29
To solve algebraically, set up two equations and then set them equal to one another.

p = price of towel
t = number of towels

Equation 1) pt = 120 => p = 120/t
Equation 2) (p + 1) * (t - 10) = 120

pt = (p + 1) * (t - 10)
pt = pt - 10p + t - 10
10 = -10p + t
10 = -10 * (120 / t) + t
10t = -1200 + t^2
t^2 - 10t - 1200 = 0
(t + 30) * (t - 40) = 0
t = - 30 or t = 40

Since t is the number of towels, it can only be a positive number, and thus t = 40. Since you want the current price of each towel, or p, divide 120 by 40 (equation 1) to get p = 3.

Alternatively, you can also plug in the answer choices to avoid algebra.

pt = 120

A) p = 1; t = 120
B) p = 2; t = 60
C) p = 3; t = 40
D) p = 4; t = 30
E) p = 12; t = 10

Just from that, you can tell that by increasing the price by $1 from $3 to $4, 10 fewer towels can be bought for $120. Thus the answer is C.
Intern
Intern
avatar
Status: Accepted - SMU, Singapore (Class of 2013)
Joined: 08 Sep 2011
Posts: 27
Location: Singapore
Concentration: Finance, General Management
GMAT 1: 620 Q46 V29
GMAT 2: 710 Q50 V35
WE: Information Technology (Computer Software)
Followers: 3

Kudos [?]: 12 [0], given: 0

Re: 600-700 level question [#permalink] New post 04 Oct 2011, 23:41
Good solutions sesamemochi, but I'd like to modify it slightly to make it faster to solve. From my experience, I would say that we must always try to form an equation in the variable that we need to calculate. This will save us one step at the end. For example, I would solve this problem as below -

Assume the current price to be x. So, as per the given information, we can form the below equation -
120/x = 120/(x+1) + 10

Solving this equation for x, we get 3 and -4
Choose 3 as price cannot be negative.

Secondly, for your alternate 'value plugging' approach, time can be saved if only the options with consecutive prices are considered. In this case 1, 2, 3, 4. But since 12 is not in the sequence, there was no need to even consider option E.

Lastly, in most cases, I find plugging of values a risky affair. Even plugging requires thinking, for example in this case even after plugging the values, only the results of consecutive price pairs matter, such as 1,2 ; 2,3 and 3,4. And imagine if option D was 5 instead of 4, then the plugging would have been useless. Moreover if someone does all the plugging and calculations and later realizes that there are no consecutive pairs to consider, it will be such a waste of time.
My 2 cents - All in all, I suggest that we use value plugging as the last resort. It is more important to know the concepts. Value plugging needs thinking too, so better apply thoughts to applying the concepts.
_________________

p!yu$h
from-620-to-710-my-gmat-story-test-date-30-oct-122547.html#p995276

Manager
Manager
avatar
Joined: 16 Feb 2012
Posts: 237
Concentration: Finance, Economics
Followers: 6

Kudos [?]: 179 [0], given: 121

GMAT ToolKit User
Re: A store currently charges the same price for each towel that [#permalink] New post 24 Mar 2012, 13:51
I don't understand how do you come from pxq =120 to (p+1) x (q-10) = 120

Please explain! Thanks!
_________________

Kudos if you like the post!

Failing to plan is planning to fail.

Expert Post
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 31304
Followers: 5364

Kudos [?]: 62542 [0], given: 9457

Re: A store currently charges the same price for each towel that [#permalink] New post 24 Mar 2012, 14:00
Expert's post
Stiv wrote:
I don't understand how do you come from pxq =120 to (p+1) x (q-10) = 120

Please explain! Thanks!


Let the current price be \(p\) and the # of towels sold at this price be \(n\). Then we would have two equations:

"If the current price of each towel were to be increased by $1, 10 fewer of the towels could be bought for $120": \(pn=120\) amd \((p+1)(n-10)=120\), so the same $120 can buy \(n\) towels for \($p\) each or \(n-1\) towels for \($(p+1)\) each.

For complete solution check this: a-store-currently-charges-the-same-price-for-each-towel-that-30571-20.html#p782872

Hope it helps.
_________________

New to the Math Forum?
Please read this: 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

GMAT Club Legend
GMAT Club Legend
User avatar
Joined: 09 Sep 2013
Posts: 8236
Followers: 419

Kudos [?]: 111 [0], given: 0

Top 10 in overall
Re: A store currently charges the same price for each towel that [#permalink] New post 15 Sep 2013, 18:35
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________

GMAT Books | GMAT Club Tests | Best Prices on GMAT Courses | GMAT Mobile App | Math Resources | Verbal Resources

Manager
Manager
avatar
Joined: 21 Aug 2013
Posts: 113
Schools: ISB '15
Followers: 2

Kudos [?]: 19 [0], given: 60

CAT Tests
Re: A store currently charges the same price for each towel that [#permalink] New post 01 Mar 2014, 03:54
Hi,
I know this is a OG question. Still from the below text how can we assume that the current P X Q = 120.

A store currently charges the same price for each towel that it sells. If the current price of each towel were to be increased by $1, 10 fewer of the towels could be bought for $120, excluding sales tax. What is the current price of each towel?
_________________

Veritas Prep - 650
MGMAT 1 590
MGMAT 2 640 (V48/Q31)

Please help the community by giving Kudos.

Expert Post
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 31304
Followers: 5364

Kudos [?]: 62542 [0], given: 9457

Re: A store currently charges the same price for each towel that [#permalink] New post 01 Mar 2014, 05:49
Expert's post
seabhi wrote:
Hi,
I know this is a OG question. Still from the below text how can we assume that the current P X Q = 120.

A store currently charges the same price for each towel that it sells. If the current price of each towel were to be increased by $1, 10 fewer of the towels could be bought for $120, excluding sales tax. What is the current price of each towel?


The price increase and quantity decrease are linked with the amount of $120, how else?

OPEN DISCUSSION OF THIS QUESTION IS HERE: a-store-currently-charges-the-same-price-for-each-towel-that-144780.html
_________________

New to the Math Forum?
Please read this: 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

Re: A store currently charges the same price for each towel that   [#permalink] 01 Mar 2014, 05:49

Go to page   Previous    1   2   [ 31 posts ] 

    Similar topics Author Replies Last post
Similar
Topics:
1 Experts publish their posts in the topic A store reduced the price of all items in the store by 10% on the firs Bunuel 3 07 Feb 2016, 09:53
Experts publish their posts in the topic The price of a coat in a certain store is $500. If the price of the co LithiumIon 2 17 Jun 2015, 21:26
6 Experts publish their posts in the topic An amusement park currently charges the same price for each ticket of Bunuel 7 13 Nov 2014, 08:42
21 Experts publish their posts in the topic A store currently charges the same price for each towel that Walkabout 11 27 Dec 2012, 04:47
2 A store’s selling price of $2240 for a certain computer would yield a monirjewel 3 28 Oct 2010, 21:28
Display posts from previous: Sort by

A store currently charges the same price for each towel that

  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 and phpBB SEO

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®.