It is currently 21 Oct 2017, 11:08

### 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

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^x + 2^x = 2^n, what is x in terms of n?

Author Message
TAGS:

### Hide Tags

Manager
Joined: 03 Jun 2010
Posts: 171

Kudos [?]: 71 [0], given: 40

Location: United States (MI)
Concentration: Marketing, General Management
If 2^x + 2^x + 2^x + 2^x = 2^n, what is x in terms of n? [#permalink]

### Show Tags

12 Jan 2011, 22:59
1
This post was
BOOKMARKED
00:00

Difficulty:

25% (medium)

Question Stats:

63% (00:32) correct 37% (00:27) wrong based on 79 sessions

### HideShow timer Statistics

If $$2^x + 2^x + 2^x + 2^x = 2^n$$, what is x in terms of n?

A. n/4

B. 4n

C. 2n

D. n - 2

E. n + 2
[Reveal] Spoiler: OA

Last edited by Bunuel on 20 May 2017, 13:35, edited 1 time in total.
Renamed the topic, edited the question and added the OA.

Kudos [?]: 71 [0], given: 40

Current Student
Joined: 27 Jul 2010
Posts: 98

Kudos [?]: 16 [1], given: 9

GMAT 1: 740 Q50 V40
Re: If 2^x + 2^x + 2^x + 2^x = 2^n, what is x in terms of n? [#permalink]

### Show Tags

13 Jan 2011, 10:00
1
KUDOS
2^x + 2^x + 2^x + 2^x = 4 * 2^x = 2^2 * 2^x = 2^(2+x)
so , if 2^(2+x)= 2^n then 2+x=n so x=n-2.

Kudos [?]: 16 [1], given: 9

Intern
Joined: 14 Dec 2010
Posts: 20

Kudos [?]: 3 [0], given: 0

Re: If 2^x + 2^x + 2^x + 2^x = 2^n, what is x in terms of n? [#permalink]

### Show Tags

20 Jan 2011, 06:29
Yep D
4(2^x)=2^n
2^2(2^x)=2^n
2^(x+2)=2^n
x+2=n
x=n-2

Posted from my mobile device

Kudos [?]: 3 [0], given: 0

Intern
Joined: 16 Mar 2010
Posts: 13

Kudos [?]: 3 [0], given: 3

Re: If 2^x + 2^x + 2^x + 2^x = 2^n, what is x in terms of n? [#permalink]

### Show Tags

20 Jan 2011, 08:21
I to am with the algebraic approach for arriving at the solution.

But if in the heat of things we forget $$a ^ m * a ^ n = a ^ {(m+n)}$$ we can substitute for x and solve

$$2^x + 2^x + 2^x + 2^x = 2^n$$

Substitute x = 1

$$2^1 + 2^1 + 2^1 + 2^1 = 2^n$$

$$8 = 2^n$$

$$n = 3$$

$$x = 1 & n = 3$$
$$x = 1 = n - 2$$

D

Kudos [?]: 3 [0], given: 3

Senior Manager
Joined: 08 Nov 2010
Posts: 394

Kudos [?]: 128 [0], given: 161

Re: If 2^x + 2^x + 2^x + 2^x = 2^n, what is x in terms of n? [#permalink]

### Show Tags

18 Feb 2011, 15:02
u can also plug x=0 and u get n=2.
than u can c on the answers
n-2 = x

2-2=0. finish...
_________________

Kudos [?]: 128 [0], given: 161

GMAT Club Legend
Joined: 09 Sep 2013
Posts: 16589

Kudos [?]: 273 [0], given: 0

Re: If 2^x + 2^x + 2^x + 2^x = 2^n, what is x in terms of n? [#permalink]

### Show Tags

20 May 2017, 05:50
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.
_________________

Kudos [?]: 273 [0], given: 0

Director
Joined: 22 May 2016
Posts: 820

Kudos [?]: 266 [1], given: 552

Re: If 2^x + 2^x + 2^x + 2^x = 2^n, what is x in terms of n? [#permalink]

### Show Tags

20 May 2017, 13:27
1
KUDOS
bumpbot , the question is missing

Kudos [?]: 266 [1], given: 552

Math Expert
Joined: 02 Sep 2009
Posts: 41894

Kudos [?]: 129127 [1], given: 12194

Re: If 2^x + 2^x + 2^x + 2^x = 2^n, what is x in terms of n? [#permalink]

### Show Tags

20 May 2017, 13:38
1
KUDOS
Expert's post
genxer123 wrote:
bumpbot , the question is missing

_____________________
_________________

Kudos [?]: 129127 [1], given: 12194

Director
Joined: 07 Dec 2014
Posts: 815

Kudos [?]: 248 [0], given: 12

If 2^x + 2^x + 2^x + 2^x = 2^n, what is x in terms of n? [#permalink]

### Show Tags

20 May 2017, 16:11
ulm wrote:
If $$2^x + 2^x + 2^x + 2^x = 2^n$$, what is x in terms of n?

A. n/4

B. 4n

C. 2n

D. n - 2

E. n + 2

4*2^x=2^n
2^2*2^x=2^n
2^2*2^1=2^3
x=1
n=3
x=n-2
D

Kudos [?]: 248 [0], given: 12

If 2^x + 2^x + 2^x + 2^x = 2^n, what is x in terms of n?   [#permalink] 20 May 2017, 16:11
Display posts from previous: Sort by