GMAT Question of the Day - Daily to your Mailbox; hard ones only

 It is currently 22 Jan 2019, 15:30

### 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 January
PrevNext
SuMoTuWeThFrSa
303112345
6789101112
13141516171819
20212223242526
272829303112
Open Detailed Calendar
• ### The winners of the GMAT game show

January 22, 2019

January 22, 2019

10:00 PM PST

11:00 PM PST

In case you didn’t notice, we recently held the 1st ever GMAT game show and it was awesome! See who won a full GMAT course, and register to the next one.
• ### Key Strategies to Master GMAT SC

January 26, 2019

January 26, 2019

07:00 AM PST

09:00 AM PST

Attend this webinar to learn how to leverage Meaning and Logic to solve the most challenging Sentence Correction Questions.

# What is the area of square ABCD?

Author Message
TAGS:

### Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 52390
What is the area of square ABCD?  [#permalink]

### Show Tags

17 Feb 2016, 02:35
1
00:00

Difficulty:

5% (low)

Question Stats:

89% (00:25) correct 11% (00:33) wrong based on 161 sessions

### HideShow timer Statistics

What is the area of square ABCD?

(1) The diagonal of square ABCD is $$5\sqrt{2}$$
(2) The perimeter of square ABCD is 20

Kudos for correct solution.

_________________
SVP
Joined: 26 Mar 2013
Posts: 2003
Re: What is the area of square ABCD?  [#permalink]

### Show Tags

18 Feb 2016, 06:58
1
Bunuel wrote:
What is the area of square ABCD?

(1) The diagonal of square ABCD is $$5\sqrt{2}$$
(2) The perimeter of square ABCD is 20

Kudos for correct solution.

Let the length of square= L

(1) The diagonal of square ABCD is $$5\sqrt{2}$$

So L= 5........> Area =5*5=25

(2) The perimeter of square ABCD is 20..............> 4L=20...? L=5
Area= 25

Intern
Joined: 30 Aug 2015
Posts: 31
Concentration: Marketing, Finance
WE: Brand Management (Manufacturing)
Re: What is the area of square ABCD?  [#permalink]

### Show Tags

18 Feb 2016, 15:45
1
Let the length of square= L

(1) The diagonal of square ABCD is 52√52

So L= 5........> Area =5*5=25

(2) The perimeter of square ABCD is 20..............> 4L=20...? L=5
Area= 25
WE KNOW THAT SQUARE FORMS 45, 45, 90 TRIANGLE , SO BASIC CONCEPT IS KNOWING ANY SINGLE SIDE WE CAN CALCULATE ALL OTHER SIDES..
_________________

Please award kudos if you like my explanation.
Thanks

Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Posts: 6826
GMAT 1: 760 Q51 V42
GPA: 3.82
Re: What is the area of square ABCD?  [#permalink]

### Show Tags

18 Feb 2016, 18:32
Forget conventional ways of solving math questions. In DS, Variable approach is the easiest and quickest way to find the answer without actually solving the problem. Remember equal number of variables and independent equations ensures a solution.

What is the area of square ABCD?

(1) The diagonal of square ABCD is 5 √2
(2) The perimeter of square ABCD is 20

In the original condition, there is 1 variable(one side of square: x) for square, which should match with the number of equations. So you need 1 equation. For 1) 1 equation, for 2) 1 equation, which is likely to make D the answer. In fact, it is 99% that D is the answer.
For 1), from √2(x)=5√2, x=5, which is unique and sufficient.
For 2), from 4x=20, x=5, which is unique and sufficient.

 For cases where we need 1 more equation, such as original conditions with “1 variable”, or “2 variables and 1 equation”, or “3 variables and 2 equations”, we have 1 equation each in both 1) and 2). Therefore, there is 59 % chance that D is the answer, while A or B has 38% chance and C or E has 3% chance. Since D is most likely to be the answer using 1) and 2) separately according to DS definition. Obviously there may be cases where the answer is A, B, C or E.
_________________

MathRevolution: Finish GMAT Quant Section with 10 minutes to spare
The one-and-only World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy.
"Only \$149 for 3 month Online Course"
"Free Resources-30 day online access & Diagnostic Test"
"Unlimited Access to over 120 free video lessons - try it yourself"

Director
Joined: 24 Nov 2015
Posts: 514
Location: United States (LA)
Re: What is the area of square ABCD?  [#permalink]

### Show Tags

04 Aug 2016, 14:26
Statement 1 gives the length of diagonal of square as 5 $$\sqrt{2}$$
so side is 5 and area =$$side^2$$ = 25
So sufficient
Statement 2 gives the perimeter as 20
perimeter = 4 * side = 20 so side is 5 and area = $$side^2$$ = 25
So sufficient
Retired Moderator
Joined: 26 Nov 2012
Posts: 592
What is the area of square ABCD?  [#permalink]

### Show Tags

04 Aug 2016, 16:56
Bunuel wrote:
What is the area of square ABCD?

(1) The diagonal of square ABCD is $$5\sqrt{2}$$
(2) The perimeter of square ABCD is 20

Kudos for correct solution.

Took 16 secs to solve..I think it's still more..

Stat 1: $$a\sqrt{2}$$(Diagonal of a sqaure) = $$5\sqrt{2}$$.
a = 5.. Sufficient..

Stat 2: 4a = 20 , a = 5..Sufficient..

Manager
Joined: 05 Apr 2014
Posts: 140
Location: India
Schools: ISB '19, Fox"19
GMAT 1: 660 Q48 V33
GPA: 3
Re: What is the area of square ABCD?  [#permalink]

### Show Tags

21 Feb 2017, 22:07
D
Statement 1 is sufficient
Side is 7
So area would be 49
Statement 2 is sufficient as well
Side is 7 as diagonal is sideroot2
So area 49

Sent from my SM-G600FY using GMAT Club Forum mobile app
Re: What is the area of square ABCD? &nbs [#permalink] 21 Feb 2017, 22:07
Display posts from previous: Sort by