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

It is currently 24 Oct 2014, 01:43

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

Decreasing the original price of an item by 25% and then

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
1 KUDOS received
Manager
Manager
User avatar
Joined: 28 May 2009
Posts: 155
Followers: 4

Kudos [?]: 102 [1] , given: 89

GMAT ToolKit User
Decreasing the original price of an item by 25% and then [#permalink] New post 04 Mar 2013, 07:13
1
This post received
KUDOS
00:00
A
B
C
D
E

Difficulty:

  75% (hard)

Question Stats:

50% (02:36) correct 50% (00:58) wrong based on 105 sessions
Decreasing the original price of an item by 25% and then decreasing the new price by z% is equivalent to decreasing the original price by

(A) 0.25(1 + \frac{3z}{100})

(B) 0.25(1 + \frac{z}{100})

(C) 0.25(1 - \frac{3z}{100})

(D) 0.75(1 - \frac{z}{100})

(E) 0.75(1 + \frac{3z}{100})

Source: Gmat Hacks 1800
[Reveal] Spoiler: OA

_________________

New to GMAT Club? Start here

Kindle Flashcards - Quant (Official Gmat Club, miguemick's Quant topics), and Verbal (Official Gmat Club) - in Kindle (azw3) format

Kaplan Promo CodeKnewton GMAT Discount CodesGMAT Pill GMAT Discount Codes
2 KUDOS received
BSchool Thread Master
User avatar
Status: Tutor
Joined: 05 Apr 2011
Posts: 431
Location: India
Concentration: Finance, Marketing
Schools: XLRI (A)
GMAT 1: 570 Q49 V19
GMAT 2: 700 Q51 V31
GPA: 3
WE: Information Technology (Computer Software)
Followers: 58

Kudos [?]: 255 [2] , given: 44

Premium Member
Re: Decreasing the original price of an item by 25% and then [#permalink] New post 04 Mar 2013, 07:24
2
This post received
KUDOS
megafan wrote:
Decreasing the original price of an item by 25% and then decreasing the new price by z% is equivalent to decreasing the original price by

(A) 0.25(1 + \frac{3z}{100})

(B) 0.25(1 + \frac{z}{100})

(C) 0.25(1 - \frac{3z}{100})

(D) 0.75(1 - \frac{z}{100})

(E) 0.75(1 + \frac{3z}{100})

Source: Gmat Hacks 1800


Suppose original Price is X
decreasing by 25%, new price is X (100-25)/100 = 0.75X
Decreasing the new price by z%, new price will be 0.75X * (100-z)/100

= 0.75*(1-(z/100)) * X
original price is decreased by
X - 0.75*(1-(z/100)) * X
= X ( 0.25 + Z*(0.75/100))
= X * 0.25 ( 1 + (3z/100))

So, answer will be A
hope it helps!
_________________

ankit
you must believe

How to start GMAT preparations?
How to Improve Quant Score?
gmatclub topic tags
Check out my GMAT debrief
Thursdays with Ron link
Looking for a Quant tutor? Check out my post for the same!

Combined Formula Sheet :
Number Properties || Word Problems and PnC || Equations, Inequalities || Geometry

How to Solve :
Statistics || Reflection of a line || Remainder Problems

Expert Post
1 KUDOS received
Verbal Forum Moderator
Verbal Forum Moderator
User avatar
Joined: 10 Oct 2012
Posts: 628
Followers: 43

Kudos [?]: 598 [1] , given: 135

Premium Member
Re: Decreasing the original price of an item by 25% and then [#permalink] New post 04 Mar 2013, 07:26
1
This post received
KUDOS
Expert's post
megafan wrote:
Decreasing the original price of an item by 25% and then decreasing the new price by z% is equivalent to decreasing the original price by

(A) 0.25(1 + \frac{3z}{100})

(B) 0.25(1 + \frac{z}{100})

(C) 0.25(1 - \frac{3z}{100})

(D) 0.75(1 - \frac{z}{100})

(E) 0.75(1 + \frac{3z}{100})



Let the initial price be 100. Initial drop is by 25%. This gives 75. Assume z=100%. Thus, the final price now will be, a 100% decrease on 75 = 0. This is equivalent to a 100% decrease on the initial price of 100. Put z = 100%, only option A matches.

A.
_________________

All that is equal and not-Deep Dive In-equality

Hit and Trial for Integral Solutions

Expert Post
1 KUDOS received
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 23400
Followers: 3611

Kudos [?]: 28872 [1] , given: 2859

Re: Decreasing the original price of an item by 25% and then [#permalink] New post 04 Mar 2013, 11:00
1
This post received
KUDOS
Expert's post
megafan wrote:
Decreasing the original price of an item by 25% and then decreasing the new price by z% is equivalent to decreasing the original price by

(A) 0.25(1 + \frac{3z}{100})

(B) 0.25(1 + \frac{z}{100})

(C) 0.25(1 - \frac{3z}{100})

(D) 0.75(1 - \frac{z}{100})

(E) 0.75(1 + \frac{3z}{100})

Source: Gmat Hacks 1800


Similar question to practice from OG: increasing-the-original-price-of-an-article-by-15-percent-127086.html

Hope it helps.
_________________

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

Manager
Manager
avatar
Joined: 18 Oct 2013
Posts: 81
Location: India
Concentration: Technology, Finance
GMAT 1: 580 Q48 V21
WE: Information Technology (Computer Software)
Followers: 2

Kudos [?]: 29 [0], given: 25

Re: Decreasing the original price of an item by 25% and then [#permalink] New post 10 Nov 2013, 10:42
Let z=50%

so equivalent change must be 62.5% .So answer is A
Senior Manager
Senior Manager
User avatar
Joined: 17 Dec 2012
Posts: 395
Location: India
Followers: 14

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

Re: Decreasing the original price of an item by 25% and then [#permalink] New post 10 Nov 2013, 16:07
Bunuel wrote:
megafan wrote:
Decreasing the original price of an item by 25% and then decreasing the new price by z% is equivalent to decreasing the original price by

(A) 0.25(1 + \frac{3z}{100})

(B) 0.25(1 + \frac{z}{100})

(C) 0.25(1 - \frac{3z}{100})

(D) 0.75(1 - \frac{z}{100})

(E) 0.75(1 + \frac{3z}{100})

Source: Gmat Hacks 1800


Similar question to practice from OG: increasing-the-original-price-of-an-article-by-15-percent-127086.html

Hope it helps.



An easy approach is to assume a convenient value for z.

1. Let it be 20%
2. The value is first reduced by 25%. So it becomes 75%
3. The above value is then reduced by 20%. So it becomes 60%
4. So the equivalent reduction is 40%

Choice A gives the same equivalent percentage i.e., 0.25(1 + 3*20/100) = 0.25 (1+0.6) = 0.4 = 40%.

If you want to confirm and have the time, you can test for 1 more value of z.
_________________

Srinivasan Vaidyaraman
Sravna Test Prep
http://www.sravna.com

Classroom Courses in Chennai
Online and Correspondence Courses

Re: Decreasing the original price of an item by 25% and then   [#permalink] 10 Nov 2013, 16:07
    Similar topics Author Replies Last post
Similar
Topics:
4 Experts publish their posts in the topic If the original price of an item in a retail store is marked singhmaharaj 4 26 Nov 2013, 06:10
2 The original price of a car was $25,200 AtifS 6 09 Mar 2010, 01:07
If a grocery shopper received $0.25 off the original price rnemani 4 03 Nov 2008, 13:27
The original price of an article was reduced by 25 percent. IHATEMELGIBSON1 8 29 Mar 2007, 10:18
The original price of an article was reduced by 25 percent. gayathri 10 17 Jan 2005, 09:18
Display posts from previous: Sort by

Decreasing the original price of an item by 25% and then

  Question banks Downloads My Bookmarks Reviews Important topics  


cron

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®.