BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem
TTP OnDemand GMAT Video Course
Featured Course

Target Test Prep GMAT OnDemand

Scott Woodbury-Stewart’s private virtual classroom — 400 hours of master-class video lessons for the GMAT Focus Edition.

  • 715+ score guarantee — highest in the industry (99th percentile)
  • 52 chapters · 1,500+ lessons · 4,000+ practice questions
  • 400 hours of video · 1,500+ instructor-led HD smartboard lessons
  • 300,000+ students accepted to Harvard, Stanford, Wharton, Booth & Sloan & more
  • 24/7 live support + weekly Zoom office hours with GMAT instructors
  • TTP AI Assist — 24/7 AI-powered virtual tutor for instant help
  • 1,200+ flashcards + AI-powered study assistant & daily calendar
  • OnDemand, LiveTeach & GMAT Bootcamp formats available
  • Also: GRE, SAT Math & Executive Assessment courses
  • MBA Admissions Consulting now available
  • 🏆 2025 EdTech Breakthrough Award: Test Prep Solution Provider of the Year
  • 200,000+ students served
  • 5-day free trial — $0 to start, no auto-billing, cancel anytime
★★★★★ 5.0 (559 reviews)
130-pt guarantee
$0 to start then $127/mo
Start Free 5-Day Trial Read 559 Reviews →

David has d books (OG16)

Expert replies
Post new topic Post Reply
Previous Topic Next Topic
Senior | Next Rank: 100 Posts
Posts: 93
Joined: Mon Apr 25, 2016 2:22 pmFollowed by: 1 member
Thanked: 1 times
by boomgoesthegmat » Thu May 19, 2016 3:45 pm

Timer

00:00

Answers

A

B

C

D

E

Stats

Difficulty—

David has d books, which is 3 times as many as Jeff and 1/2 as many as Paula. How many books do the three of them have altogether, in terms of d ?

A) (5/6)d
B) (7/3)d
C) (10/3)d
D) (7/2)d
E) (9/2)d

OA: C
Last edited by boomgoesthegmat on Thu May 19, 2016 4:30 pm, edited 1 time in total.
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Source: — Problem Solving |

GMAT/MBA Expert

User avatar
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] » Thu May 19, 2016 4:28 pm
Hi boomgoesthegmat,

To start, there's a typo in your transcription - it's supposed to read "...and 1/2 as many as Paula...."

We can answer this question by TESTing VALUES or by doing algebra...

IF...
Jeff = 2 books
David = 6 books = D books
Paula = 12 books

The total number of books = 2+6+12 = 20

So we're looking for an answer that equals 20 when D=6. There's only one answer that matches...

Final Answer: C

GMAT assassins aren't born, they're made,
Rich
Contact Rich at [email protected]
Image
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 16207
Joined: Mon Dec 08, 2008 6:26 pmFollowed by: 1268 members
Location: Vancouver, BC
Thanked: 5254 times
GMAT Score:770

David has d books (OG16)

by Brent@GMATPrepNow » Fri May 20, 2016 9:01 am
boomgoesthegmat wrote:David has d books, which is 3 times as many as Jeff and 1/2 as many as Paula. How many books do the three of them have altogether, in terms of d ?

A) (5/6)d
B) (7/3)d
C) (10/3)d
D) (7/2)d
E) (9/2)d

OA: C
Rich has demonstrated the INPUT-OUTPUT approach. Here's an algebraic approach.

d = # of books that David has

David has 3 times as many books as Jeff
So, d/3 = # of books that Jeff has

David has 1/2 as many books as Paula
So, 2d = # of books that Paula has

How many books do the three of them have altogether, in terms of d ?
TOTAL # of books = d + d/3 + 2d
= 3d/3 + d/3 + 6d/3
= [spoiler]10d/3[/spoiler]
= C

---------------------------------

Rich and I have demonstrated the two methods (Algebraic and Input-Output) for solving a question type I call Variables in the Answer Choices.
If you'd like more information on these approaches, we have some videos:
- Variables in the Answer Choices - https://www.gmatprepnow.com/module/gmat- ... /video/933
- Tips for the Algebraic Approach - https://www.gmatprepnow.com/module/gmat- ... /video/934
- Tips for the Input-Output Approach - https://www.gmatprepnow.com/module/gmat- ... /video/935

Here are some more questions to practice with:
- https://www.beatthegmat.com/what-mistak ... 76293.html
- https://www.beatthegmat.com/car-dealer- ... 74136.html
- https://www.beatthegmat.com/ps-rate-times-t276107.html
- https://www.beatthegmat.com/to-find-the ... 73338.html
- https://www.beatthegmat.com/y-dollars-f ... 73031.html
- https://www.beatthegmat.com/meters-in-x ... 73854.html
- https://www.beatthegmat.com/a-better-ex ... 79396.html


Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
Image
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
User avatar
GMAT Instructor
Posts: 1462
Joined: Thu Apr 09, 2015 9:34 amFollowed by: 22 members
Location: New York, NY
Thanked: 39 times

by Jeff@TargetTestPrep » Fri May 18, 2018 11:30 am
boomgoesthegmat wrote:David has d books, which is 3 times as many as Jeff and 1/2 as many as Paula. How many books do the three of them have altogether, in terms of d ?

A) (5/6)d
B) (7/3)d
C) (10/3)d
D) (7/2)d
E) (9/2)d
We can let the number of books David has = d, the number of books Jeff has = j, and the number of books Paula has = p

We are given that David has 3 times as many books as Jeff. We can now express this in an equation.

d = 3j

d/3 = j

We are also given that David has 1/2 as many books as Paula. We can also express this in an equation.

d = (1/2)p

2d = p

We need to determine, in terms of d, the sum of the number of books for David, Jeff, and Paula. Thus, we have:

d + d/3 + 2d

3d/3 + d/3 + 6d/3 = 10d/3 = (10/3)d

Answer: C

Jeffrey Miller
Head of GMAT Instruction
[email protected]

Image

See why Target Test Prep is rated 5 out of 5 stars on BEAT the GMAT. Read our reviews
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Post new topic Post Reply
• Page 1 of 1