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

 It is currently 26 Jan 2020, 14:31

### 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

# In ΔJKL shown above, what is the length of segment JL ?

Author Message
TAGS:

### Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 60646
In ΔJKL shown above, what is the length of segment JL ?  [#permalink]

### Show Tags

26 Apr 2019, 02:59
00:00

Difficulty:

5% (low)

Question Stats:

87% (00:34) correct 13% (00:43) wrong based on 262 sessions

### HideShow timer Statistics

In ΔJKL shown above, what is the length of segment JL ?

(1) JK = 10
(2) KL = 5

DS83602.01
OG2020 NEW QUESTION

Attachment:

2019-04-26_1358.png [ 6.45 KiB | Viewed 2278 times ]

_________________
examPAL Representative
Joined: 07 Dec 2017
Posts: 1155
Re: In ΔJKL shown above, what is the length of segment JL ?  [#permalink]

### Show Tags

26 Apr 2019, 15:15
1
The Logical approach to this question will use the fact that in order to find the measurements of all of the sides of a 30-60-90 triangle (or a 45-45-90 triangle) all ee need is one side.
In this question each of the statements gives us the length of one side, and thus they each suffice on their own. The correct answer is (D).

Posted from my mobile device
_________________
Manager
Joined: 14 Apr 2017
Posts: 70
Location: Hungary
GMAT 1: 760 Q50 V42
WE: Education (Education)
Re: In ΔJKL shown above, what is the length of segment JL ?  [#permalink]

### Show Tags

27 Apr 2019, 17:24
1
Bunuel wrote:

In ΔJKL shown above, what is the length of segment JL ?

(1) JK = 10
(2) KL = 5

DS83602.01
OG2020 NEW QUESTION

$$\triangle{JKL}$$ is a 30-60-90 degree special right triangle with a ratio of $$1:\sqrt{3}:2$$ for its corresponding sides. The original question: $$JL=?$$

1) We know that $$JK=10$$, the angle opposite $$JK$$ is $$90^{\circ}$$, and the angle opposite $$JL$$ is $$60^{\circ}$$, so $$JL:10=\sqrt{3}:2$$. Thus, we could get a unique value to answer the original question. $$\implies$$ Sufficient

2) We know that $$KL=5$$, the angle opposite $$KL$$ is $$30^{\circ}$$, and the angle opposite $$JL$$ is $$60^{\circ}$$, so $$JL:5=\sqrt{3}:1$$. Thus, we could get a unique value to answer the original question. $$\implies$$ Sufficient

_________________
My book with my solutions to all 230 PS questions in OG2018:
Zoltan's solutions to OG2018 PS
EMPOWERgmat Instructor
Status: GMAT Assassin/Co-Founder
Affiliations: EMPOWERgmat
Joined: 19 Dec 2014
Posts: 15985
Location: United States (CA)
GMAT 1: 800 Q51 V49
GRE 1: Q170 V170
Re: In ΔJKL shown above, what is the length of segment JL ?  [#permalink]

### Show Tags

12 May 2019, 14:06
Hi All,

Based on the triangle JKL above, we know that we're dealign with a 30/60/90 right triangle. We're asked for the length of segment JL. The 30/60/90 triangle has a specific 'ratio of sides' (re: X : X√3 : 2X), meaning that if we know 1 of the sides, then we can determine the lengths of the other 2. By extension, depending on the information in the two Facts, we could potentially answer this question without doing any math at all.

(1) JK = 10

Fact 1 gives us the hypotenuse of the triangle, so we can figure out the exact values of the other two sides.
Fact 1 is SUFFICIENT

(2) KL = 5
Fact 2 gives us the 'short leg' of the triangle, so we can figure out the exact values of the other two sides.
Fact 2 is SUFFICIENT

GMAT assassins aren't born, they're made,
Rich
_________________
Contact Rich at: Rich.C@empowergmat.com

The Course Used By GMAT Club Moderators To Earn 750+

souvik101990 Score: 760 Q50 V42 ★★★★★
ENGRTOMBA2018 Score: 750 Q49 V44 ★★★★★
Target Test Prep Representative
Status: Founder & CEO
Affiliations: Target Test Prep
Joined: 14 Oct 2015
Posts: 9143
Location: United States (CA)
Re: In ΔJKL shown above, what is the length of segment JL ?  [#permalink]

### Show Tags

12 May 2019, 19:09
Bunuel wrote:

In ΔJKL shown above, what is the length of segment JL ?

(1) JK = 10
(2) KL = 5

DS83602.01
OG2020 NEW QUESTION

Attachment:
2019-04-26_1358.png

We see that we have a 30-60-90 right triangle, which has sides in the following ratio:

x : x√3 : 2x

Thus, if we know the length of either JK or KL, we can determine the length of JL.

Statement One Alone:

JK = 10

Since JK = 10, 2x = 10, so x = 5, and thus JL = 5√3.

Statement one is sufficient to answer the question.

Statement Two Alone:

KL = 5

Since KL = 5, JL = 5√3.

Statement two alone is sufficient to answer the question.

_________________

# Scott Woodbury-Stewart

Founder and CEO

Scott@TargetTestPrep.com
181 Reviews

5-star rated online GMAT quant
self study course

See why Target Test Prep is the top rated GMAT quant course on GMAT Club. Read Our Reviews

If you find one of my posts helpful, please take a moment to click on the "Kudos" button.

GMAT Club Legend
Joined: 12 Sep 2015
Posts: 4228
Re: In ΔJKL shown above, what is the length of segment JL ?  [#permalink]

### Show Tags

13 May 2019, 10:47
Top Contributor
Bunuel wrote:

In ΔJKL shown above, what is the length of segment JL ?

(1) JK = 10
(2) KL = 5

DS83602.01
OG2020 NEW QUESTION

Attachment:
2019-04-26_1358.png

KEY CONCEPT: 30-60-90 triangles are known as special right triangles, and we know quite a bit about this kind of triangle

Target question: What is the length of segment JL ?

Statement 1: JK = 10

Compare ΔJKL with the BASE 30-60-90 triangle.
Their corresponding hypotenuses are 10 and 2, which tells us that ΔJKL is 5 times the size of BASE 30-60-90 triangle.
So, the length of segment JL will be 5 times the size its corresponding side (with length √3)
In other words, JL must have length 5√3
Since we can answer the target question with certainty, statement 1 is SUFFICIENT

Statement 2: KL = 5

The corresponding sides here have lengths 5 and 1, which tells us that ΔJKL is 5 times the size of BASE 30-60-90 triangle.
So, JL must have length 5√3
Since we can answer the target question with certainty, statement 2 is SUFFICIENT

Cheers,
Brent
_________________
Test confidently with gmatprepnow.com
Re: In ΔJKL shown above, what is the length of segment JL ?   [#permalink] 13 May 2019, 10:47
Display posts from previous: Sort by