Last visit was: 13 Dec 2024, 09:52 It is currently 13 Dec 2024, 09:52
Home
GMAT
Messages
Tests
Schools
Reviews
Social
Chat
My Profile
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.
Go to My Error Log Learn more
Close
Request Expert Reply
Confirm Cancel
Back to Forum
Create Topic
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 13 Dec 2024
Posts: 97,873
Own Kudos:
685,572
 []
Given Kudos: 88,268
Products:
GMAT Club Tests Forum Quiz
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 97,873
Kudos: 685,572
 []
If the price of coffee, p, doubles every week for 4 weeks, triples a 05 Apr 2017, 04:56
Kudos
Add Kudos
1
Bookmarks
Bookmark this Post
00:00
Start Timer
Pause Timer
Resume Timer
Show Answer
Hide
Show
History
E
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!

Difficulty:

45% (medium)

Question Stats:

67% (01:51) correct 33% (02:00) wrong based on 91 sessions

History

Date
Time
Result
Not Attempted Yet
If the price of coffee, p, doubles every week for 4 weeks, triples a week later, and finally quadruples a week after that, which of the following represents the price of coffee at the end of period, in terms of p?

A. 15p
B. 7*8*p
C. 7*2^4*p
D. 3*4*8*p
E. 12*2^4*p
ShowHide Answer
Official Answer
E
avatar
gvvsnraju@1
avatar
Joined: 03 Jan 2016
Last visit: 09 Dec 2018
Posts: 50
Own Kudos:
18
Given Kudos: 83
Location: India
WE:Engineering (Energy)
Posts: 50
Kudos: 18
If the price of coffee, p, doubles every week for 4 weeks, triples a 05 Apr 2017, 05:50
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Initial Price = p
First Week Price = 2p.
Sec Week Price = 4p
Third week Price = 8p
Fourth week = 16p
Fifth week = 3X16 p= 3* 16 p
Sixth week = 4*3*16p = E

Narayana raju
User avatar
KarishmaB
User avatar
Joined: 16 Oct 2010
Last visit: 13 Dec 2024
Posts: 15,546
Own Kudos:
70,237
 []
Given Kudos: 449
Location: Pune, India
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 15,546
Kudos: 70,237
 []
If the price of coffee, p, doubles every week for 4 weeks, triples a 05 Apr 2017, 10:18
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Since the price doubles every week, it means it gets multiplied by 2 every week.

Price after 4 weeks = 2 * 2 * 2 * 2 * p = 16p
Price after 5 weeks = 3 * 16p
Price after 6 weeks = 4 * 3 * 16p = 12 * 16p

Answer (E)
User avatar
IdiomSavant
User avatar
Joined: 14 Sep 2016
Last visit: 03 May 2018
Posts: 46
Own Kudos:
39
Given Kudos: 119
Concentration: Finance, Economics
Schools: Boston U '20 Carroll '20
Schools: Boston U '20 Carroll '20
Posts: 46
Kudos: 39
If the price of coffee, p, doubles every week for 4 weeks, triples a 05 Apr 2017, 12:55
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Bunuel
If the price of coffee, p, doubles every week for 4 weeks, triples a week later, and finally quadruples a week after that, which of the following represents the price of coffee at the end of period, in terms of p?

A. 15p
B. 7*8*p
C. 7*2^4*p
D. 3*4*8*p
E. 12*2^4*p

If you are bad at creating equations just pick an easy number to work with.

let P = $1

Week 1 = $2
Week 2 = $4
Week 3 = $8
Week 4 = $16
Week 5 = $48
Week 6 = $192

Testing equations you will find that E fits this.

12*2^4*p
12*2^4*1
12*16*1
192
User avatar
JeffTargetTestPrep
User avatar
Target Test Prep Representative
Joined: 04 Mar 2011
Last visit: 05 Jan 2024
Posts: 3,023
Own Kudos:
7,209
 []
Given Kudos: 1,646
Status:Head GMAT Instructor
Affiliations: Target Test Prep
Expert reply
Posts: 3,023
Kudos: 7,209
 []
If the price of coffee, p, doubles every week for 4 weeks, triples a 11 Apr 2017, 12:45
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Bunuel
If the price of coffee, p, doubles every week for 4 weeks, triples a week later, and finally quadruples a week after that, which of the following represents the price of coffee at the end of period, in terms of p?

A. 15p
B. 7*8*p
C. 7*2^4*p
D. 3*4*8*p
E. 12*2^4*p

If the initial price of coffee is p, after week one it's 2p, after week two it’s 4p, after week 3 it’s 8p, and after week 4 it’s 16p.

Since the price triples a week later, the new price is (3)(16p), and since it quadruples the following week, it's (4)(3)(16p) = 12*2^4*p .

Answer: E
avatar
matthewsmith_89
avatar
Joined: 06 Dec 2016
Last visit: 06 Oct 2017
Posts: 195
Own Kudos:
60
Given Kudos: 10
Posts: 195
Kudos: 60
If the price of coffee, p, doubles every week for 4 weeks, triples a 11 Apr 2017, 18:18
Kudos
Add Kudos
Bookmarks
Bookmark this Post
The price of coffee, p doubles every week for 4 weeks
2 x 2 x 2 x 2 = 16
Triples a week later
16 x 3
Quadruples a week later
16 x 3 x 4 = 192

Now do process elimination
Only E works out to 192
Proof:

12 x 2^4 = 12 x 16
= 192

Therefore, the answer is E
Moderator:
Bunuel
Math Expert
97872 posts