GMAT Question of the Day: Daily via email | Daily via Instagram New to GMAT Club? Watch this Video

 It is currently 26 May 2020, 23:13

### 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

# (49^2 - 35^2)/14 =

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

### Hide Tags

IIMA, IIMC School Moderator
Joined: 04 Sep 2016
Posts: 1425
Location: India
WE: Engineering (Other)
(49^2 - 35^2)/14 =  [#permalink]

### Show Tags

Updated on: 10 Dec 2017, 19:52
1
8
00:00

Difficulty:

5% (low)

Question Stats:

84% (01:19) correct 16% (02:08) wrong based on 158 sessions

### HideShow timer Statistics

$$\frac{(49^2 - 35^2)}{14} =$$

A. 74
B. 76
C. 78
D. 79
E. 84

_________________
It's the journey that brings us happiness not the destination.

Feeling stressed, you are not alone!!

Originally posted by adkikani on 10 Dec 2017, 17:51.
Last edited by Bunuel on 10 Dec 2017, 19:52, edited 1 time in total.
Renamed the topic, edited the question
Math Expert
Joined: 02 Aug 2009
Posts: 8592
(49^2 - 35^2)/14 =  [#permalink]

### Show Tags

10 Dec 2017, 18:03
1
1
adkikani wrote:
$$(49^2 - 35^2)$$ /14 =

A. 74
B. 76
C. 78
D. 79
E. 84

Ofcourse it is $$a^2-b^2=(a-b)(a+b)$$..
Here (49-35)(49+35)/14=14*84/14=84..

Do your calculations or observer the properties of number involved, of the calculations are difficult, and answer in a sec, ...

Both 49 and 35 have a 7 in them..
So we will get 7*7 in the product, one 7 from addition and other from subtraction..
One 7 gets cancelled out with 7 in 14..
Our ANSWER should be a MULTIPLE of 7..
Only E left
_________________
GMAT Club Legend
Joined: 11 Sep 2015
Posts: 4875
Location: Canada
GMAT 1: 770 Q49 V46
Re: (49^2 - 35^2)/14 =  [#permalink]

### Show Tags

10 Dec 2017, 19:56
Top Contributor
1
adkikani wrote:
$$\frac{(49^2 - 35^2)}{14} =$$

A. 74
B. 76
C. 78
D. 79
E. 84

(49² - 35²)/14 = (49 + 35)(49 - 35)/14
= (84)(14)/14
= 84
= E

RELATED VIDEO FROM OUR COURSE

_________________
Test confidently with gmatprepnow.com
Senior SC Moderator
Joined: 22 May 2016
Posts: 3848
(49^2 - 35^2)/14 =  [#permalink]

### Show Tags

10 Dec 2017, 21:33
adkikani wrote:
$$\frac{(49^2 - 35^2)}{14} =$$

A. 74
B. 76
C. 78
D. 79
E. 84

$$\frac{(49^2 - 35^2)}{14}=?$$

Start writing what you know, breaking numbers into pieces: $$49^2 = (49)(49)$$, for example. And there are factors of 7 everywhere.

Factor everything, with cancellation in mind if you can, to reduce errors.

$$\frac{(49)(49) - (35)(35)}{(2*7)}=$$

$$\frac{(7*7*7*7) - (7*5*7*5)}{(2*7)}=$$

Notice two 7s in numerator's two terms, hence

$$\frac{49(7*7 - 5*5)}{(2*7)}=$$

$$\frac{49(49 - 25)}{(2*7)}=\frac{49*(24)}{2*7}=$$

$$\frac{(7*7)(2*12)}{2*7}= (7*12) = 84$$

Answer E
_________________
Visit SC Butler, here! Get two SC questions to practice, whose links you can find by date.

Our lives begin to end the day we become silent about things that matter. -- Dr. Martin Luther King, Jr.
Veritas Prep GMAT Instructor
Joined: 16 Oct 2010
Posts: 10451
Location: Pune, India
Re: (49^2 - 35^2)/14 =  [#permalink]

### Show Tags

13 Dec 2017, 19:58
adkikani wrote:
$$\frac{(49^2 - 35^2)}{14} =$$

A. 74
B. 76
C. 78
D. 79
E. 84

Responding to a pm:
Quote:
Can this be also solved using unit digits?

I am not sure what you mean. How do you intend to use unit's digit concept here?

You are probably confusing it with using units digit concept for remainders when dividing by 2, 5 or 10. Check it out here:

https://www.veritasprep.com/blog/2015/1 ... questions/
https://www.veritasprep.com/blog/2015/1 ... ns-part-2/
_________________
Karishma
Veritas Prep GMAT Instructor

Learn more about how Veritas Prep can help you achieve a great GMAT score by checking out their GMAT Prep Options >
Non-Human User
Joined: 09 Sep 2013
Posts: 14980
Re: (49^2 - 35^2)/14 =  [#permalink]

### Show Tags

09 Feb 2019, 13:22
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.
_________________
Re: (49^2 - 35^2)/14 =   [#permalink] 09 Feb 2019, 13:22

# (49^2 - 35^2)/14 =

 new topic post reply Question banks Downloads My Bookmarks Reviews Important topics

 Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne