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

It is currently 15 Sep 2014, 21:11

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 shopkeeper increases the price of an article by X%

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
1 KUDOS received
Intern
Intern
avatar
Joined: 12 Oct 2012
Posts: 24
Followers: 0

Kudos [?]: 3 [1] , given: 1

A shopkeeper increases the price of an article by X% [#permalink] New post 28 Oct 2012, 20:45
1
This post received
KUDOS
3
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

  45% (medium)

Question Stats:

70% (02:12) correct 30% (02:36) wrong based on 10 sessions
A shopkeeper increases the price of an article by X% and then decreases it by X%. As a result the price of the article is reduced by $180. After one more such change the price is further reduced by $153 Find the original price of the article.

A. $1200
B. $1100
C. $1400
D. $1000
E. $1500
[Reveal] Spoiler: OA
Expert Post
3 KUDOS received
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 26591
Followers: 3487

Kudos [?]: 26170 [3] , given: 2706

Re: A shopkeeper increases the price of an article by X% [#permalink] New post 29 Oct 2012, 01:15
3
This post received
KUDOS
Expert's post
chris93 wrote:
A shopkeeper increases the price of an article by X% and then decreases it by X%. As a result the price of the article is reduced by $180. After one more such change the price is further reduced by $153 Find the original price of the article.

A. $1200
B. $1100
C. $1400
D. $1000
E. $1500


Let the net decrease in price after x% increase and x% decrease be a%. Also, let the initial price be $p.

Given:
After a% decrease the price of the article is reduced by $180 --> pa=180;
After one more such change the price is further reduced by $153. After the first decrease the pice became $(p-180), thus (p-180)a=153 --> pa-180a=153.

Since pa=180, then 180-180a=153 --> a=15% --> p*0.15=180 --> p=1,200.

Answer: A.

Hope it's clear.
_________________

NEW TO MATH FORUM? PLEASE READ THIS: ALL YOU NEED FOR QUANT!!!

PLEASE READ AND FOLLOW: 11 Rules for Posting!!!

RESOURCES: [GMAT MATH BOOK]; 1. Triangles; 2. Polygons; 3. Coordinate Geometry; 4. Factorials; 5. Circles; 6. Number Theory; 7. Remainders; 8. Overlapping Sets; 9. PDF of Math Book; 10. Remainders; 11. GMAT Prep Software Analysis NEW!!!; 12. SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) NEW!!!; 12. Tricky questions from previous years. NEW!!!;

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?
25 extra-hard Quant Tests

Get the best GMAT Prep Resources with GMAT Club Premium Membership

Intern
Intern
avatar
Joined: 18 May 2012
Posts: 15
Followers: 0

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

Re: A shopkeeper increases the price of an article by X% [#permalink] New post 16 Nov 2012, 11:48
Bunuel wrote:
chris93 wrote:
A shopkeeper increases the price of an article by X% and then decreases it by X%. As a result the price of the article is reduced by $180. After one more such change the price is further reduced by $153 Find the original price of the article.

A. $1200
B. $1100
C. $1400
D. $1000
E. $1500


Let the net decrease in price after x% increase and x% decrease be a%. Also, let the initial price be $p.

Given:
After a% decrease the price of the article is reduced by $180 --> pa=180;
After one more such change the price is further reduced by $153. After the first decrease the pice became $(p-180), thus (p-180)a=153 --> pa-180a=153.

Since pa=180, then 180-180a=153 --> a=15% --> p*0.15=180 --> p=1,200.

Answer: A.

Hope it's clear.


Could you explain how you got from 180 - 180a = 153 to 15% please, thank you
Intern
Intern
avatar
Joined: 01 Jun 2012
Posts: 21
Location: United States
Concentration: Nonprofit
GMAT 1: 720 Q48 V43
GPA: 3.83
Followers: 0

Kudos [?]: 7 [0], given: 15

Re: A shopkeeper increases the price of an article by X% [#permalink] New post 16 Nov 2012, 17:23
Bunuel wrote:
chris93 wrote:
A shopkeeper increases the price of an article by X% and then decreases it by X%. As a result the price of the article is reduced by $180. After one more such change the price is further reduced by $153 Find the original price of the article.

A. $1200
B. $1100
C. $1400
D. $1000
E. $1500


Let the net decrease in price after x% increase and x% decrease be a%. Also, let the initial price be $p.

Given:
After a% decrease the price of the article is reduced by $180 --> pa=180;
After one more such change the price is further reduced by $153. After the first decrease the pice became $(p-180), thus (p-180)a=153 --> pa-180a=153.

Since pa=180, then 180-180a=153 --> a=15% --> p*0.15=180 --> p=1,200.

Answer: A.

Hope it's clear.


Hi Bunuel,

If you increase an amount by x% and then decrease the amount by x%, is the net decrease always equal to a constant a%? You seem to assume that in your reasoning.

Thanks!
Eric
Expert Post
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 26591
Followers: 3487

Kudos [?]: 26170 [0], given: 2706

Re: A shopkeeper increases the price of an article by X% [#permalink] New post 17 Nov 2012, 05:12
Expert's post
egiles wrote:
Bunuel wrote:
chris93 wrote:
A shopkeeper increases the price of an article by X% and then decreases it by X%. As a result the price of the article is reduced by $180. After one more such change the price is further reduced by $153 Find the original price of the article.

A. $1200
B. $1100
C. $1400
D. $1000
E. $1500


Let the net decrease in price after x% increase and x% decrease be a%. Also, let the initial price be $p.

Given:
After a% decrease the price of the article is reduced by $180 --> pa=180;
After one more such change the price is further reduced by $153. After the first decrease the pice became $(p-180), thus (p-180)a=153 --> pa-180a=153.

Since pa=180, then 180-180a=153 --> a=15% --> p*0.15=180 --> p=1,200.

Answer: A.

Hope it's clear.


Hi Bunuel,

If you increase an amount by x% and then decrease the amount by x%, is the net decrease always equal to a constant a%? You seem to assume that in your reasoning.

Thanks!
Eric


Yes, it does not depend on the amount. I mean that whether initial amount is $10 or $20, if you increase both by x% and then decrease both by x%, you'll get the net decrease of the same percentage:

For example if you increase both 10 and 100 by 10% and then decrease both by 10%, you'll get the net decrease of 1% for both amounts.

Hope it's clear.
_________________

NEW TO MATH FORUM? PLEASE READ THIS: ALL YOU NEED FOR QUANT!!!

PLEASE READ AND FOLLOW: 11 Rules for Posting!!!

RESOURCES: [GMAT MATH BOOK]; 1. Triangles; 2. Polygons; 3. Coordinate Geometry; 4. Factorials; 5. Circles; 6. Number Theory; 7. Remainders; 8. Overlapping Sets; 9. PDF of Math Book; 10. Remainders; 11. GMAT Prep Software Analysis NEW!!!; 12. SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) NEW!!!; 12. Tricky questions from previous years. NEW!!!;

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?
25 extra-hard Quant Tests

Get the best GMAT Prep Resources with GMAT Club Premium Membership

Current Student
avatar
Joined: 25 Jun 2012
Posts: 71
Location: India
WE: General Management (Energy and Utilities)
Followers: 2

Kudos [?]: 38 [0], given: 15

Re: A shopkeeper increases the price of an article by X% [#permalink] New post 17 Nov 2012, 08:34
Hi,
Is there any other method to solve this problem....if someone dont get the logic in the solution provided by Bunuel?
Intern
Intern
avatar
Joined: 17 May 2012
Posts: 5
Followers: 0

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

Re: A shopkeeper increases the price of an article by X% [#permalink] New post 19 Nov 2012, 02:35
Hi Bunuel,
I have a doubt,U have equated the changed price value to 180 rather than equating the change in price.

pa is the final value after reduction in price,so to represent the change it should be p-pa=180.isnt it?

Please Correct me if i m wrong
Expert Post
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 26591
Followers: 3487

Kudos [?]: 26170 [0], given: 2706

Re: A shopkeeper increases the price of an article by X% [#permalink] New post 19 Nov 2012, 02:52
Expert's post
kona wrote:
Hi Bunuel,
I have a doubt,U have equated the changed price value to 180 rather than equating the change in price.

pa is the final value after reduction in price,so to represent the change it should be p-pa=180.isnt it?

Please Correct me if i m wrong


We are told that after a% decrease the price of the article is reduced by $180, which means that a% of p is $180 --> pa=180.
_________________

NEW TO MATH FORUM? PLEASE READ THIS: ALL YOU NEED FOR QUANT!!!

PLEASE READ AND FOLLOW: 11 Rules for Posting!!!

RESOURCES: [GMAT MATH BOOK]; 1. Triangles; 2. Polygons; 3. Coordinate Geometry; 4. Factorials; 5. Circles; 6. Number Theory; 7. Remainders; 8. Overlapping Sets; 9. PDF of Math Book; 10. Remainders; 11. GMAT Prep Software Analysis NEW!!!; 12. SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) NEW!!!; 12. Tricky questions from previous years. NEW!!!;

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?
25 extra-hard Quant Tests

Get the best GMAT Prep Resources with GMAT Club Premium Membership

Intern
Intern
avatar
Joined: 08 Nov 2012
Posts: 3
Followers: 0

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

Re: A shopkeeper increases the price of an article by X% [#permalink] New post 22 Nov 2012, 03:04
hi, i was confused by the question:
A shopkeeper increases the price of an article by X% and then decreases it by X%. As a result the price of the article is reduced by $180. After one more such change the price is further reduced by $153 Find the original price of the article.

I think the question run in the following logic:
1. Price increase by x%
2. Price decrease by x %
3. After step 1 and step 2, price is reduced by $180 from the original price
4. Price increase by x%
5. Price decrease by x%
6. After step 4 and 5, price is reduced by $153 further.

Is it incorrect??
Re: A shopkeeper increases the price of an article by X%   [#permalink] 22 Nov 2012, 03:04
    Similar topics Author Replies Last post
Similar
Topics:
Experts publish their posts in the topic Increasing the original price of an article by 15% and then chiccufrazer1 3 09 Mar 2013, 20:48
1 Experts publish their posts in the topic Increasing the original price of an article by 15 percent fiendex 3 05 Feb 2012, 15:25
If the price increased by X% from 2001 to 2002 and by Y% asmit123 6 21 Mar 2011, 20:16
The price was increased by x % and then decreased by y %. Is marcodonzelli 6 02 Mar 2008, 03:22
The price of a certain commodity increased at a rate of x% bmwhype2 2 27 Dec 2007, 06:54
Display posts from previous: Sort by

A shopkeeper increases the price of an article by X%

  Question banks Downloads My Bookmarks Reviews Important topics  


GMAT Club MBA Forum Home| About| Privacy Policy| 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®.