(165)^2 - (164)^2 = : GMAT Problem Solving (PS)
Check GMAT Club Decision Tracker for the Latest School Decision Releases http://gmatclub.com/AppTrack

 It is currently 22 Jan 2017, 07:51

### 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

# (165)^2 - (164)^2 =

Author Message
TAGS:

### Hide Tags

Manager
Joined: 06 Aug 2011
Posts: 59
Concentration: Entrepreneurship, Finance
GPA: 3.87
Followers: 0

Kudos [?]: 20 [0], given: 1

### Show Tags

10 Mar 2012, 22:53
8
This post was
BOOKMARKED
00:00

Difficulty:

5% (low)

Question Stats:

81% (02:13) correct 19% (01:05) wrong based on 237 sessions

### HideShow timer Statistics

(165)^2 - (164)^2 =

A. 1
B. 100
C. 229
D. 329
E. 349
[Reveal] Spoiler: OA
SVP
Joined: 16 Nov 2010
Posts: 1672
Location: United States (IN)
Concentration: Strategy, Technology
Followers: 33

Kudos [?]: 514 [2] , given: 36

### Show Tags

10 Mar 2012, 22:55
2
KUDOS
CLearly :

a^2 - b^2 = (a+b) * (a-b)

=> (165)^2 - (164)^2 = (165 + 164) * (165 - 164) = 329 * 1

_________________

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

GMAT Club Premium Membership - big benefits and savings

Manager
Joined: 06 Aug 2011
Posts: 59
Concentration: Entrepreneurship, Finance
GPA: 3.87
Followers: 0

Kudos [?]: 20 [0], given: 1

Re: (165)^2 - (164)^2 = [#permalink]

### Show Tags

10 Mar 2012, 23:07
Thanks!

... But what would you do if the problem were written more like this:

(165)^3 - (163)^3 =

or:

(165)^2 - (163)^3 =
SVP
Joined: 16 Nov 2010
Posts: 1672
Location: United States (IN)
Concentration: Strategy, Technology
Followers: 33

Kudos [?]: 514 [0], given: 36

Re: (165)^2 - (164)^2 = [#permalink]

### Show Tags

10 Mar 2012, 23:15
(165)^3 - (163)^3

You can use the formula a^3 - b^3

(165)^2 - (163)^3

Expand (163)^3 as (165 - 2)^3 to simplify further.
_________________

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

GMAT Club Premium Membership - big benefits and savings

Manager
Joined: 06 Aug 2011
Posts: 59
Concentration: Entrepreneurship, Finance
GPA: 3.87
Followers: 0

Kudos [?]: 20 [0], given: 1

Re: (165)^2 - (164)^2 = [#permalink]

### Show Tags

10 Mar 2012, 23:24
I think I'll have to go to YouTube or something for the ^2 x ^3, but I think I get the ^3 x ^3:

(165)^2 - (164)^2 = (165)^3 - (164)^3 = 329
Manager
Status: And the Prep starts again...
Joined: 03 Aug 2010
Posts: 138
Followers: 2

Kudos [?]: 48 [1] , given: 20

Re: (165)^2 - (164)^2 = [#permalink]

### Show Tags

16 Apr 2012, 06:10
1
KUDOS
Stoneface wrote:
(165)^2 - (164)^2 =

A. 1
B. 100
C. 229
D. 329
E. 349

Difference between square of two consecutive numbers is = the sum of the of the two consecutive numbers

165+164 = 329

D
_________________

My First Blog on my GMAT Journey

Arise, Awake and Stop not till the goal is reached

SVP
Status: The Best Or Nothing
Joined: 27 Dec 2012
Posts: 1858
Location: India
Concentration: General Management, Technology
WE: Information Technology (Computer Software)
Followers: 47

Kudos [?]: 1935 [0], given: 193

Re: (165)^2 - (164)^2 = [#permalink]

### Show Tags

27 Feb 2014, 20:32
Stoneface wrote:
(165)^2 - (164)^2 =

A. 1
B. 100
C. 229
D. 329
E. 349

Using the formula:

(a+1)^2 - a^2 = 2a+1

So, Answer = 164*2 + 1
= 328+1 = 329 = Answer = D
_________________

Kindly press "+1 Kudos" to appreciate

Intern
Joined: 17 Aug 2014
Posts: 5
Followers: 0

Kudos [?]: 0 [0], given: 13

Re: (165)^2 - (164)^2 = [#permalink]

### Show Tags

28 Aug 2014, 15:37
Where can these rules for this particular problem be found?
Intern
Joined: 27 Aug 2014
Posts: 30
GMAT Date: 09-27-2014
Followers: 1

Kudos [?]: 10 [0], given: 25

Re: (165)^2 - (164)^2 = [#permalink]

### Show Tags

28 Aug 2014, 21:30
GMATcrusher wrote:
Where can these rules for this particular problem be found?

See Bunuel's signature for the Math exponents resources link.
Intern
Joined: 27 Aug 2014
Posts: 30
GMAT Date: 09-27-2014
Followers: 1

Kudos [?]: 10 [0], given: 25

Re: (165)^2 - (164)^2 = [#permalink]

### Show Tags

28 Aug 2014, 21:34
Stoneface wrote:
I think I'll have to go to YouTube or something for the ^2 x ^3, but I think I get the ^3 x ^3:

(165)^2 - (164)^2 = (165)^3 - (164)^3 = 329

No, the expansion is different for both, please see the exponents theory in the Math chapter resources section.

(165)^2 - (164)^2 = 329

(165)^3 - (164)^3 = 81181
Math Expert
Joined: 02 Sep 2009
Posts: 36597
Followers: 7093

Kudos [?]: 93444 [1] , given: 10563

Re: (165)^2 - (164)^2 = [#permalink]

### Show Tags

29 Aug 2014, 04:11
1
KUDOS
Expert's post
GMATcrusher wrote:
Where can these rules for this particular problem be found?

Check Tips and hints on Algebra here: algebra-tips-and-hints-175003.html

Also, I suggest you to go through the following post ALL YOU NEED FOR QUANT and check links in my signature below.

Hope it helps.
_________________
GMAT Club Legend
Joined: 09 Sep 2013
Posts: 13500
Followers: 577

Kudos [?]: 163 [0], given: 0

Re: (165)^2 - (164)^2 = [#permalink]

### Show Tags

28 Nov 2015, 15:01
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.
_________________
Intern
Joined: 28 Oct 2015
Posts: 24
Followers: 0

Kudos [?]: 2 [0], given: 218

Re: (165)^2 - (164)^2 = [#permalink]

### Show Tags

22 Jan 2016, 09:42
I solved it slightly different:

165^2-(165-1)^2= 165^2-(165^2+1^2-2*165*1)= 165-165-1+330= 329
Re: (165)^2 - (164)^2 =   [#permalink] 22 Jan 2016, 09:42
Display posts from previous: Sort by