If, in the figure above, ABCD is a rectangular region

Expert replies

Previous Topic Next Topic

AbeNeedsAnswers: Master | Next Rank: 500 Posts; Posts: 394; Joined: Sun Jul 02, 2017 10:59 amFollowed by: 5 members; Thanked: 1 times

by AbeNeedsAnswers » Sun May 05, 2019 9:27 pm

Timer

00:00

Answers

Stats

Difficulty—

If, in the figure above, ABCD is a rectangular region, what is the value of the ratio of (area of triangle EDA)/(area of triangle EBC)?

(1) AD = 4
(2) AE = 2 and EB = 4

B

Source: Official Guide 2020

Like this post

Source: Beat The GMAT — Data Sufficiency | Sun May 05, 2019 9:27 pm

GMAT/MBA Expert

[email protected]: Elite Legendary Member; Posts: 10392; Joined: Sun Jun 23, 2013 6:38 pmFollowed by: 511 members; Location: Palo Alto, CA; Thanked: 2867 times; GMAT Score:800

by [email protected] » Sun May 12, 2019 12:23 pm

Hi All,

We're told that in the figure above, ABCD is a rectangular region. We're asked for the value of the ratio of (area of triangle EDA)/(area of triangle EBC)? This question is based on a couple of Geometry rules. It's worth noting that all 3 triangles (EDA, EBC and EDC) all have the SAME height (so the height of the triangles is actually IRRELEVENT to the question that is asked - as that number will 'cancel out' in the numerator and denominator of the fraction). Thus we ultimately need to know how the two 'bases' of EDA and EBC relate to one another to answer this question.

(1) AD = 4

Fact 1 gives us the height of the triangles, but that does not impact the question at all. The calculation would be:
(1/2)(Base of EDA)(4) / (1/2)(Based of EBC)(4) = ?
(Base of EDA) / (Base of EBC) = ?
Fact 1 is INSUFFICIENT

(2) AE = 2 and EB = 4

Fact 2 gives us the exact lengths of the two 'bases' - and that's all we need to answer the question. The answer would be 2/4 = 1/2
Fact 2 is SUFFICIENT

Final Answer: B

GMAT assassins aren't born, they're made,
Rich

Contact Rich at [email protected]

Like this post

GMAT/MBA Expert

Scott@TargetTestPrep: GMAT Instructor; Posts: 8139; Joined: Sat Apr 25, 2015 10:56 amFollowed by: 29 members; Location: Los Angeles, CA; Thanked: 43 times

Re: If, in the figure above, ABCD is a rectangular region

by Scott@TargetTestPrep » Wed May 12, 2021 7:31 am

AbeNeedsAnswers wrote: ↑
Sun May 05, 2019 9:27 pm

If, in the figure above, ABCD is a rectangular region, what is the value of the ratio of (area of triangle EDA)/(area of triangle EBC)?

(1) AD = 4
(2) AE = 2 and EB = 4

B

Source: Official Guide 2020

Solution:

Question Stem Analysis:

We need to determine the ratio of the area of triangle EDA to that of triangle EBC. Notice the two triangles have the same height. Therefore, we are really determining the ratio of AE to BE.

Statement One Alone:

Knowing AD (the height of triangle EDA) does not allow us to determine the desired ratio. Statement one alone is not sufficient.

Statement Two Alone:

Recall that in the stem analysis, the ratio of area of triangle EDA to that of triangle EBC is equal to the ratio of AE to BE. Therefore, knowing AE and BE is sufficient to determine the desired ratio. In fact, (area of triangle EDA)/(area of triangle EBC) = AE/BE = 2/4 = 1/2. Statement two alone is sufficient.

Answer: B

Scott Woodbury-Stewart
Founder and CEO
[email protected]

See why Target Test Prep is rated 5 out of 5 stars on BEAT the GMAT. Read our reviews

Like this post

Post new topic Post Reply

• Page 1 of 1

GMAT Course Reviews

560 reviews

1168 reviews

431 reviews

359 reviews

147 reviews

5/5

5 Star (560 Reviews)

"Target Test Prep is the closest to the official version of the GMAT exam, about 99% accuracy in terms of the quality and quantity of information. The course has excellently created singular sets of focused lessons and tests for every possible topic that one could come across in the official GMAT exam."

"The TTP course maximizes the efficiency of the time you spend studying. It will take time and effort but I could almost guarantee that if you complete the course exactly as it is laid out you will get an amazing score. They also have a very responsive team willing to help with any questions you might have."

"TTP has two things that I think no other test prep company offers: A teaching approach that reinforces understanding and an attitude that will give you the mental preparedness needed to succeed on the test. TTP gives you a deep understanding of the concept you need to know while teaching you how to think."

Write a Review