It is currently 18 Nov 2017, 05:30

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

The price of a chip falls by approximately 67% every year

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

Hide Tags

1 KUDOS received
Intern
Intern
avatar
Joined: 09 Mar 2013
Posts: 10

Kudos [?]: 14 [1], given: 8

Location: India
The price of a chip falls by approximately 67% every year [#permalink]

Show Tags

New post 17 May 2013, 00:23
1
This post received
KUDOS
1
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

(N/A)

Question Stats:

100% (00:59) correct 0% (00:00) wrong based on 17 sessions

HideShow timer Statistics

The price of a chip falls by approximately 67% every year. In approximately how many years will the price of an $81 chip become $1?


I got his question in a document and it doesnt contain any options. Can you help me to resolve this.

Kudos [?]: 14 [1], given: 8

Expert Post
3 KUDOS received
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 42249

Kudos [?]: 132567 [3], given: 12326

Re: The price of a chip falls by approximately 67% every year [#permalink]

Show Tags

New post 17 May 2013, 00:33
3
This post received
KUDOS
Expert's post
rohanchowdhary wrote:
The price of a chip falls by approximately 67% every year. In approximately how many years will the price of an $81 chip become $1?


I got his question in a document and it doesnt contain any options. Can you help me to resolve this.


67%=~2/3, which means that the price of a chip becomes 1/3 of the price in a year.

In 1 year the price will be 81*1/3=$27;
In 2 year the price will be 27*1/3=$9;
In 3 year the price will be 9*1/3=$3;
In 4 year the price will be 3*1/3=$1.

Hope it helps.
_________________

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 [?]: 132567 [3], given: 12326

Intern
Intern
avatar
Joined: 09 Mar 2013
Posts: 10

Kudos [?]: 14 [0], given: 8

Location: India
Re: The price of a chip falls by approximately 67% every year [#permalink]

Show Tags

New post 17 May 2013, 00:52
+1 Kudos Brunel.

I never though in this way, this si a new way i can drive on to my result.

Kudos [?]: 14 [0], given: 8

2 KUDOS received
Intern
Intern
avatar
Joined: 04 May 2013
Posts: 18

Kudos [?]: 12 [2], given: 39

Location: Azerbaijan
Concentration: Finance, General Management
GMAT 1: 710 Q49 V38
GMAT ToolKit User
Re: The price of a chip falls by approximately 67% every year [#permalink]

Show Tags

New post 22 May 2013, 07:55
2
This post received
KUDOS
P0 = 81 (price of the chip at 0 moment)
P1 = 1/3 * P0 (67% price decrease means new price = 1/3 of the old price)
P(k+1) = P0 * (1/3)^k
81 * (1/3) ^ k = 1 leads to (1/3)^k = 1/81 = (1/3)^4 so k = 4

Kudos [?]: 12 [2], given: 39

Non-Human User
User avatar
Joined: 09 Sep 2013
Posts: 15697

Kudos [?]: 281 [0], given: 0

Premium Member
Re: The price of a chip falls by approximately 67% every year [#permalink]

Show Tags

New post 22 Oct 2015, 08:18
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

Kudos [?]: 281 [0], given: 0

Expert Post
1 KUDOS received
SVP
SVP
User avatar
G
Joined: 12 Sep 2015
Posts: 1840

Kudos [?]: 2593 [1], given: 362

Location: Canada
Re: The price of a chip falls by approximately 67% every year [#permalink]

Show Tags

New post 22 Oct 2015, 11:45
1
This post received
KUDOS
Expert's post
Bunuel is using something I call a Growth Table approach. So, rather than trying to formulate the correct answer at once, we can just take the time to list successive values until we get to where we need to be.

For more on this, check out our free video - http://www.gmatprepnow.com/module/gmat- ... /video/929
Afterwards, you can practice with this question - http://www.gmatprepnow.com/module/gmat- ... /video/930

Cheers,
Brent
_________________

Brent Hanneson – Founder of gmatprepnow.com

Image

Kudos [?]: 2593 [1], given: 362

Director
Director
User avatar
G
Joined: 23 Jan 2013
Posts: 603

Kudos [?]: 27 [0], given: 41

Schools: Cambridge'16
Re: The price of a chip falls by approximately 67% every year [#permalink]

Show Tags

New post 27 Oct 2015, 23:13
we need to find membership in Geometric progression

1 - searched number
81 - first term
1/3 - r (common ratio)

1=81*1/3^(n-1)
1/3^(n-1)=1/81

n-1=4 meaning that 1 will come after 4th year

Kudos [?]: 27 [0], given: 41

Re: The price of a chip falls by approximately 67% every year   [#permalink] 27 Oct 2015, 23:13
Display posts from previous: Sort by

The price of a chip falls by approximately 67% every year

  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®.