Last visit was: 16 May 2025, 14:24 It is currently 16 May 2025, 14:24
Close
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
Your Progress

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
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Close
Request Expert Reply
Confirm Cancel
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 16 May 2025
Posts: 101,469
Own Kudos:
724,731
 [2]
Given Kudos: 93,528
Products:
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 101,469
Kudos: 724,731
 [2]
Kudos
Add Kudos
2
Bookmarks
Bookmark this Post
User avatar
GMATinsight
User avatar
Major Poster
Joined: 08 Jul 2010
Last visit: 16 May 2025
Posts: 6,309
Own Kudos:
Given Kudos: 127
Status:GMAT/GRE Tutor l Admission Consultant l On-Demand Course creator
Location: India
GMAT: QUANT+DI EXPERT
Schools: IIM (A) ISB '24
GMAT 1: 750 Q51 V41
WE:Education (Education)
Products:
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Schools: IIM (A) ISB '24
GMAT 1: 750 Q51 V41
Posts: 6,309
Kudos: 15,334
Kudos
Add Kudos
Bookmarks
Bookmark this Post
User avatar
Siak0730
User avatar
Kellogg School Moderator
Joined: 25 Aug 2015
Last visit: 16 Apr 2025
Posts: 65
Own Kudos:
Given Kudos: 81
Location: India
Schools: ISB '25 (A)
GMAT Focus 1: 655 Q85 V82 DI80
GMAT 1: 640 Q50 V26
GMAT 2: 660 Q47 V34
GPA: 3.0
Schools: ISB '25 (A)
GMAT Focus 1: 655 Q85 V82 DI80
GMAT 2: 660 Q47 V34
Posts: 65
Kudos: 93
Kudos
Add Kudos
Bookmarks
Bookmark this Post
User avatar
BrentGMATPrepNow
User avatar
Major Poster
Joined: 12 Sep 2015
Last visit: 13 May 2024
Posts: 6,761
Own Kudos:
Given Kudos: 799
Location: Canada
Expert
Expert reply
Posts: 6,761
Kudos: 33,595
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Bunuel
What is the value of \(\frac{1}{a} + \frac{1}{b} + \frac{1}{c}\) ?


(1) \(a + b = \frac{5}{6}\)

(2) \(\frac{bc + ac + ab}{abc} = \frac{12}{13}\)


DS21203

Target question: What is the value of \(\frac{1}{a} + \frac{1}{b} + \frac{1}{c}\) ?

Statement 1: \(a + b = \frac{5}{6}\)
Since we have no information about the value of c, there's no way to answer the target question with certainty
Statement 1 is NOT SUFFICIENT

Statement 2: \(\frac{bc + ac + ab}{abc} = \frac{12}{13}\)

Key concept: \(\frac{w+x+y}{z} = \frac{w}{z} + \frac{x}{z} + \frac{y}{z}\)

So we can take: \(\frac{bc + ac + ab}{abc} = \frac{12}{13}\)

And rewrite the fractions as follows: \(\frac{bc}{abc} + \frac{ac}{abc} + \frac{ab}{abc}= \frac{12}{13}\)

Simplify each fraction to get: \(\frac{1}{a} + \frac{1}{b} + \frac{1}{c}= \frac{12}{13}\)

Voila!! The answer to the target question is 12/13

Since we can answer the target question with certainty, statement 2 is SUFFICIENT

Answer: B

Cheers,
Brent
User avatar
Kinshook
User avatar
Major Poster
Joined: 03 Jun 2019
Last visit: 16 May 2025
Posts: 5,594
Own Kudos:
Given Kudos: 161
Location: India
GMAT 1: 690 Q50 V34
WE:Engineering (Transportation)
Products:
GMAT 1: 690 Q50 V34
Posts: 5,594
Kudos: 5,010
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Bunuel
What is the value of \(\frac{1}{a} + \frac{1}{b} + \frac{1}{c}\) ?


(1) \(a + b = \frac{5}{6}\)

(2) \(\frac{bc + ac + ab}{abc} = \frac{12}{13}\)


DS21203

Asked: What is the value of \(\frac{1}{a} + \frac{1}{b} + \frac{1}{c}\) ?


(1) \(a + b = \frac{5}{6}\)
Since c is unknown
NOT SUFFICIENT

(2) \(\frac{bc + ac + ab}{abc} = \frac{12}{13}\)
\(\frac{1}{a} + \frac{1}{b} + \frac{1}{c} = \frac{12}{13}\)
SUFFICIENT

IMO B
User avatar
NitishJain
User avatar
IESE School Moderator
Joined: 11 Feb 2019
Last visit: 05 Jan 2025
Posts: 269
Own Kudos:
Given Kudos: 53
Posts: 269
Kudos: 185
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Nothing is available in the question stem, let's analyze the statements:

Statement I:: a + b = 5/6

We can write it as 1/3 + 1/2, so a and b can be 1/2, 1/3 or vice versa but we don't need exact values for a & b but still value for c is not available.

Hence NOT SUFFICIENT

A & D gone.

STATEMENT II:: bc+ac+ab/abc=12/13

Let's separate out the numerator ==> bc/abc + ac/abc + ab/abc = 12/13
==> 1/a + 1/b + 1/c = 12/13
SUFFICIENT

Hence B
User avatar
japo17
Joined: 06 Aug 2019
Last visit: 23 Jun 2021
Posts: 10
Own Kudos:
Given Kudos: 29
Posts: 10
Kudos: 6
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Question is solved if we find the value of a, b and c. Statement 1 is not sufficient as we are missing information about c. Statement 2 is sufficient. if we are careful enough to separate each fraction and simplify as they use the same denominator. After this simplification we get the value of the expression the problem is asking for.

Answer is B.


Posted from my mobile device
User avatar
bumpbot
User avatar
Non-Human User
Joined: 09 Sep 2013
Last visit: 04 Jan 2021
Posts: 36,854
Own Kudos:
Posts: 36,854
Kudos: 983
Kudos
Add Kudos
Bookmarks
Bookmark this Post
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.
Moderator:
Math Expert
101468 posts