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

It is currently 07 Jul 2015, 16:17

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

If the price increased by X% from 2001 to 2002 and by Y%

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
Intern
Intern
avatar
Joined: 08 Mar 2011
Posts: 48
Followers: 0

Kudos [?]: 10 [0], given: 4

GMAT ToolKit User
If the price increased by X% from 2001 to 2002 and by Y% [#permalink] New post 21 Mar 2011, 20:16
00:00
A
B
C
D
E

Difficulty:

  55% (hard)

Question Stats:

62% (02:05) correct 38% (01:40) wrong based on 13 sessions
If the price increased by X% from 2001 to 2002 and by Y% from 2002 to 2003,what is the % increase from 2001 to 2003?
1. XY = 30
2. 100X + 100Y + XY = 800
[Reveal] Spoiler: OA
Director
Director
avatar
Status: Matriculating
Affiliations: Chicago Booth Class of 2015
Joined: 03 Feb 2011
Posts: 926
Followers: 13

Kudos [?]: 234 [0], given: 123

Reviews Badge
Re: percent problem [#permalink] New post 21 Mar 2011, 21:13
This is a trap called "lone wolf". Wolves are loner. The question will imply that you will need two equations to solve since there are two variables. However we don't need two equations. Back to the question. If you consider the general formula for percentage change is
X+y+xy/100
S2 reduces to this form . Hence sufficient
Posted from my mobile device Image
Intern
Intern
avatar
Joined: 08 Mar 2011
Posts: 48
Followers: 0

Kudos [?]: 10 [0], given: 4

GMAT ToolKit User
Re: percent problem [#permalink] New post 21 Mar 2011, 21:36
Thanks again.
Illustrated the general formula with values...can understand now.
Will have to memorize the formula...
Manager
Manager
avatar
Joined: 24 Nov 2010
Posts: 209
Location: United States (CA)
Concentration: Technology, Entrepreneurship
Schools: Ross '15, Duke '15
Followers: 2

Kudos [?]: 43 [0], given: 7

GMAT ToolKit User
Re: percent problem [#permalink] New post 21 Mar 2011, 21:36
Assume price in 2001 = 100
--> price in 2002 = 100(1+x/100) =100 + x
--> price in 2003 = (100+x)(1+y/100) = 100 + x + y + xy/100

from 2) x + y + xy/100 =8 --> sufficient.
1) is not sufficient.

it would of course be faster if one remembered the formula.
Manager
Manager
avatar
Joined: 05 Jan 2011
Posts: 178
Followers: 3

Kudos [?]: 40 [0], given: 8

Re: percent problem [#permalink] New post 21 Mar 2011, 22:35
asmit123 wrote:
If the price increased by X% from 2001 to 2002 and by Y% from 2002 to 2003,what is the % increase from 2001 to 2003?
1. XY = 30
2. 100X + 100Y + XY = 800

Price 2001 =P
=>Price in 2002, P + x% of P = P + Px/100 = P(1 + x/100)
=> Price in 2003, P(1 + x/100)(1 + y/100)

Percentage Increase =>(P ((1 + x/100)(1 + y/100) -1)/P) *100
=>(((1+X/100)(1+Y/100))-1 ) *100
=>(100+X)(100+Y)-100
=>100X+100Y+XY+10000-100
=>800+10000-100

Hence B
SVP
SVP
avatar
Joined: 16 Nov 2010
Posts: 1680
Location: United States (IN)
Concentration: Strategy, Technology
Followers: 31

Kudos [?]: 352 [0], given: 36

Premium Member Reviews Badge
Re: percent problem [#permalink] New post 22 Mar 2011, 00:54
%age increase = {P(1+x/100)(1+y/100) - P}/P

where P is the original price.

(10000 + 100y + 100x + xy)/100000 - 1

Clearly, the answer is B.
_________________

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

GMAT Club Premium Membership - big benefits and savings

Director
Director
avatar
Joined: 01 Feb 2011
Posts: 760
Followers: 14

Kudos [?]: 73 [0], given: 42

Re: percent problem [#permalink] New post 22 Mar 2011, 18:04
rephrasing question we have x+y+(xy/100) and thats what we need to find.

1. Not sufficient . there are different possible x and y that satisfy the given condition.

2. Sufficient . as we have the expression in similar form.

Answer is B.
Re: percent problem   [#permalink] 22 Mar 2011, 18:04
    Similar topics Author Replies Last post
Similar
Topics:
2 Price increased by M% from 1991 to 1992 and by N% from 1992 tonebeeze 2 03 Jan 2011, 18:16
2 Experts publish their posts in the topic If the price increased by x% from 2001 to 2002 and by y% fro amitanand 4 18 Jan 2010, 00:29
1 Price increased by M% from 1991 to 1992 and by N% from 1992 bmwhype2 3 01 Nov 2007, 07:07
Price increased by X% from 2001 to 2002 and by Y% from 2002 GK_Gmat 8 11 Sep 2007, 00:42
Price increased by M% from 1991 to 1992 and by N% from 1992 Hermione 3 02 Dec 2006, 07:20
Display posts from previous: Sort by

If the price increased by X% from 2001 to 2002 and by Y%

  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®.