It is currently 19 Oct 2017, 13:28

### 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

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# If 2^x - 2^x-2=3(2^13), what is the value of X? A.9 B.11

 post reply Question banks Downloads My Bookmarks Reviews Important topics
Author Message
Intern
Joined: 08 Nov 2005
Posts: 11

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

Location: Beijing, China
If 2^x - 2^x-2=3(2^13), what is the value of X? A.9 B.11 [#permalink]

### Show Tags

25 Apr 2006, 05:50
00:00

Difficulty:

(N/A)

Question Stats:

100% (00:03) correct 0% (00:00) wrong based on 2 sessions

### HideShow timer Statistics

This topic is locked. If you want to discuss this question please re-post it in the respective forum.

If 2^x - 2^x-2=3(2^13), what is the value of X?

A.9
B.11
C.13
D.15
E.17

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

Intern
Joined: 02 Mar 2006
Posts: 21

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

### Show Tags

25 Apr 2006, 06:03
solving the given equation,

2^x (3/4) = 3 * (2^13)

x = 15

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

Intern
Joined: 08 Nov 2005
Posts: 11

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

Location: Beijing, China

### Show Tags

25 Apr 2006, 06:54
klsrikanth wrote:
solving the given equation,

2^x (3/4) = 3 * (2^13)

x = 15

please explain how you got this equation and how to solve.

thanks

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

Manager
Joined: 23 Jan 2006
Posts: 192

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

### Show Tags

25 Apr 2006, 06:56
I get
2^x (1/2) = 3(2^13)

2^x - 2^(x-2) = 3(2^13)
2^x - 2^x * 2^-2 = 3(2^13)
factor out 2^x:
2^x(1-1/2) = 3(2^13)
2^x(1/2) = 3(2^13)

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

Manager
Joined: 23 Jan 2006
Posts: 192

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

### Show Tags

25 Apr 2006, 07:17
Argh. nevermind.
I get it now as klsrikanth explained

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

Intern
Joined: 02 Mar 2006
Posts: 21

Kudos [?]: 2 [1], given: 0

### Show Tags

25 Apr 2006, 07:40
1
This post received
KUDOS
gvogelei wrote:
klsrikanth wrote:
solving the given equation,

2^x (3/4) = 3 * (2^13)

x = 15

please explain how you got this equation and how to solve.

thanks

Give equation 2^x - 2^x-2

takin 2^x common out of the equation

we get, 2^x ( 1- 2^(-2))

2^x (3/4)

Kudos [?]: 2 [1], given: 0

Manager
Joined: 27 Mar 2006
Posts: 136

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

### Show Tags

25 Apr 2006, 19:23
I get 15 as well

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

Intern
Joined: 08 Nov 2005
Posts: 11

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

Location: Beijing, China

### Show Tags

25 Apr 2006, 20:18
OA is D.

Good Work....Thanks

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

Director
Joined: 10 Oct 2005
Posts: 713

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

Location: Madrid
Re: PS - Exponents GMATPrep 2 [#permalink]

### Show Tags

25 Apr 2006, 21:38
gvogelei wrote:
If 2^x - 2^x-2=3(2^13), what is the value of X?

A.9
B.11
C.13
D.15
E.17

Here is my approach
{2^(x-2)}*{(2^2)-1}=3*(2^13)
2^(x-2)*3=3*2^13
2^(x-2)=2^13
x=15
_________________

IE IMBA 2010

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

Re: PS - Exponents GMATPrep 2   [#permalink] 25 Apr 2006, 21:38
Display posts from previous: Sort by

# If 2^x - 2^x-2=3(2^13), what is the value of X? A.9 B.11

 post reply Question banks Downloads My Bookmarks Reviews Important topics

 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®.