It is currently 10 Dec 2017, 19:25

### 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

# A square mirror has exactly half the area of the rectangular wall on w

Author Message
TAGS:

### Hide Tags

Manager
Joined: 13 Jun 2012
Posts: 145

Kudos [?]: 90 [0], given: 335

Location: United States
WE: Supply Chain Management (Computer Hardware)
A square mirror has exactly half the area of the rectangular wall on w [#permalink]

### Show Tags

10 Mar 2015, 14:54
1
This post was
BOOKMARKED
00:00

Difficulty:

5% (low)

Question Stats:

85% (01:16) correct 15% (01:39) wrong based on 65 sessions

### HideShow timer Statistics

A square mirror has exactly half the area of the rectangular wall on which it is hung. If each side of the mirror is 42 inches and the width of the wall is 56 inches, what is the length of the wall, in inches?

(A) 84
(B) 72
(C) 70
(D) 63
(E) 56
[Reveal] Spoiler: OA

Last edited by Bunuel on 11 Mar 2015, 04:19, edited 1 time in total.

Kudos [?]: 90 [0], given: 335

Manager
Joined: 24 Nov 2014
Posts: 177

Kudos [?]: 239 [1], given: 21

GMAT 1: 800 Q51 V51
Re: A square mirror has exactly half the area of the rectangular wall on w [#permalink]

### Show Tags

10 Mar 2015, 17:39
1
KUDOS
Expert's post
Turkish wrote:
A square mirror has exactly half the area of the rectangular wall on which it is hung. If each side of the mirror is 42 inches and the width of the wall is 56 inches, what is the length of the wall, in inches?

(A) 84
(B) 72
(C) 70
(D) 63
(E) 56

Just to be cute and do this without too many calculations, we could factor 42 into 2 * 3 * 7 and 56 into 2 * 2 * 2 * 7.

So the area of the mirror would be (2 * 3 * 7)(2 * 3 * 7), and double the area of the mirror is therefore $$2^3 * 3^2 * 7^2$$.

For the wall we already have $$2^3 * 7$$ for the width. So the length must be $$3^2 * 7$$ = 63

Choose
[Reveal] Spoiler:
D
.
_________________

Marty Murray
GMAT Coach
m.w.murray@hotmail.com
http://infinitemindprep.com

Kudos [?]: 239 [1], given: 21

Manager
Joined: 13 Jun 2012
Posts: 145

Kudos [?]: 90 [0], given: 335

Location: United States
WE: Supply Chain Management (Computer Hardware)
Re: A square mirror has exactly half the area of the rectangular wall on w [#permalink]

### Show Tags

11 Mar 2015, 02:04
Since the mirror is 42 inches in all sides, it must be a square. Area of a square is A=a^2; 42^2=1764.Area of rectangle is double of that 2 *1764=3528.Now A=lw and we need find w so A/l=w ; 3528/56= 62 Answer!

Kudos [?]: 90 [0], given: 335

Non-Human User
Joined: 09 Sep 2013
Posts: 14956

Kudos [?]: 287 [0], given: 0

Re: A square mirror has exactly half the area of the rectangular wall on w [#permalink]

### Show Tags

11 Aug 2017, 04:41
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 [?]: 287 [0], given: 0

Manager
Joined: 06 Jul 2014
Posts: 104

Kudos [?]: 40 [0], given: 179

Location: India
Concentration: Finance, Entrepreneurship
GMAT 1: 640 Q48 V30
Re: A square mirror has exactly half the area of the rectangular wall on w [#permalink]

### Show Tags

11 Aug 2017, 07:46
2*42*42=56*length
2*42*42= units digit of 8. Answer 63

Kudos [?]: 40 [0], given: 179

Re: A square mirror has exactly half the area of the rectangular wall on w   [#permalink] 11 Aug 2017, 07:46
Display posts from previous: Sort by