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

 It is currently 23 Jan 2019, 20:27

### 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
• ### 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.
• ### Free GMAT Number Properties Webinar

January 27, 2019

January 27, 2019

07:00 AM PST

09:00 AM PST

Attend this webinar to learn a structured approach to solve 700+ Number Properties question in less than 2 minutes.

# In the diagram given below, ∠ABD = ∠CDB = ∠PQD = 90°. If AB: CD = 3: 1

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

### Hide Tags

Senior Manager
Joined: 24 Apr 2016
Posts: 331
In the diagram given below, ∠ABD = ∠CDB = ∠PQD = 90°. If AB: CD = 3: 1  [#permalink]

### Show Tags

10 Mar 2017, 11:39
2
00:00

Difficulty:

65% (hard)

Question Stats:

54% (02:48) correct 46% (02:27) wrong based on 51 sessions

### HideShow timer Statistics

In the diagram given below, ∠ABD = ∠CDB = ∠PQD = 90°. If AB: CD = 3: 1, the ratio of CD: PQ

a). 1: 0.69
b). 1: 0.75
c). 1: 0.72
d). 1: 0.50
e). None of these

Attachments

diagram.PNG [ 4.52 KiB | Viewed 2535 times ]

VP
Joined: 05 Mar 2015
Posts: 1003
Re: In the diagram given below, ∠ABD = ∠CDB = ∠PQD = 90°. If AB: CD = 3: 1  [#permalink]

### Show Tags

10 Mar 2017, 18:28
1
quantumliner wrote:
In the diagram given below, ∠ABD = ∠CDB = ∠PQD = 90°. If AB: CD = 3: 1, the ratio of CD: PQ

a). 1: 0.69
b). 1: 0.75
c). 1: 0.72
d). 1: 0.50
e). None of these

triangles ABD & PQD && CDB &PQB are similar
and AB/CD=3/1=AB=3CD-------((a)

AB/PQ = BD/QD-----(b)
CD/PQ = BD/BQ----(c)

substituting value BD from (c) to (b)
CD*BQ=AB*QD
substituting value AB from (a)
BQ/QD=3/1
thus BD/BQ= 4/3 (as BD=BQ+QD)

or CD/PQ= 4/3 =1/0.75
Ans B
Director
Joined: 12 Nov 2016
Posts: 730
Location: United States
Schools: Yale '18
GMAT 1: 650 Q43 V37
GRE 1: Q157 V158
GPA: 2.66
Re: In the diagram given below, ∠ABD = ∠CDB = ∠PQD = 90°. If AB: CD = 3: 1  [#permalink]

### Show Tags

11 Mar 2017, 21:57
1
Okay I completely don't understand the proportionality theorem- kudos for help
Senior Manager
Joined: 24 Apr 2016
Posts: 331
Re: In the diagram given below, ∠ABD = ∠CDB = ∠PQD = 90°. If AB: CD = 3: 1  [#permalink]

### Show Tags

12 Mar 2017, 00:30
In the figure, Let BQ = a and DQ = b

Triangle ABD and triangle PQD are similar. Therefore, PQ/AB = b/(a+b)

Also triangle CBD and triangle PBQ are similar. Therefore, PQ/CD = a/(a+b)

Dividing the second equality by the first, we get. AB/CD = a/b = 3

Therefore, CD/PQ = (a+b)/a = 4/3 = 1 : 0.75
Non-Human User
Joined: 09 Sep 2013
Posts: 9466
Re: In the diagram given below, ∠ABD = ∠CDB = ∠PQD = 90°. If AB: CD = 3: 1  [#permalink]

### Show Tags

23 Sep 2018, 11:05
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: In the diagram given below, ∠ABD = ∠CDB = ∠PQD = 90°. If AB: CD = 3: 1 &nbs [#permalink] 23 Sep 2018, 11:05
Display posts from previous: Sort by

# In the diagram given below, ∠ABD = ∠CDB = ∠PQD = 90°. If AB: CD = 3: 1

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

 Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.