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

Redeem

GMAT Prep - Data Sufficiency Question

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Newbie | Next Rank: 10 Posts
Posts: 4
Joined: Thu Nov 01, 2012 10:19 am

GMAT Prep - Data Sufficiency Question

by Ette004 » Sun Dec 30, 2012 11:57 am
Hey guys,

I'm just analyzing my mistakes in the GMAT Prep test and I can't figure out the solution for the following question:

In a Pet-Shop 1/3 of the pets are dogs and 1/5 of the pets are birds. How many of the dogs are pets?
(1) There are 30 birds in the Pet-Shop
(2) There are 20 more Birds than dogs in the Pet-Shop

The correct answer is D - Both statements seperately are sufficient.
(1) is clear to me - but I'm struggling to see how (2) is sufficient to identify the number of dogs.

Do you guys have an idea?

Cheers
Thomas
Top
Source: — Data Sufficiency |

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 3835
Joined: Fri Apr 02, 2010 10:00 pm
Location: Milpitas, CA
Thanked: 1854 times
Followed by:523 members
GMAT Score:770

by Anurag@Gurome » Sun Dec 30, 2012 9:25 pm
Ette004 wrote:Hey guys,

I'm just analyzing my mistakes in the GMAT Prep test and I can't figure out the solution for the following question:

In a Pet-Shop 1/3 of the pets are dogs and 1/5 of the pets are birds. How many of the dogs are pets?
(1) There are 30 birds in the Pet-Shop
(2) There are 20 more Birds than dogs in the Pet-Shop

The correct answer is D - Both statements seperately are sufficient.
(1) is clear to me - but I'm struggling to see how (2) is sufficient to identify the number of dogs.

Do you guys have an idea?

Cheers
Thomas
The correct question is:

At a certain pet shop, 1/3 of the pets are dogs and 1/5 of the pets are birds. How many of the pets are dogs?

(1) There are 30 birds at the pet shop.
(2) There are 20 more dogs than birds at the pet shop.

Let the total number of pets = P, birds = B and dogs = D.
Then from the question we have,
B = P/5
D = P/3

(1) No. of birds = 30
P/5 = 30, so we can find P and hence we can find the no. of dogs; SUFFICIENT.

(2) There are 20 more dogs than birds implies B + 20 = D
So, P/5 + 20 = P/3
Here again we can find P and hence we can find number of dogs; SUFFICIENT.

The correct answer is D.
Anurag Mairal, Ph.D., MBA
GMAT Expert, Admissions and Career Guidance
Gurome, Inc.
1-800-566-4043 (USA)

Join Our Facebook Groups
GMAT with Gurome
https://www.facebook.com/groups/272466352793633/
Admissions with Gurome
https://www.facebook.com/groups/461459690536574/
Career Advising with Gurome
https://www.facebook.com/groups/360435787349781/
Top
User avatar
Senior | Next Rank: 100 Posts
Posts: 47
Joined: Wed Nov 21, 2012 10:40 pm
Thanked: 4 times

by ritind » Thu Jan 03, 2013 12:34 am
Ette004 wrote:Hey guys,

I'm just analyzing my mistakes in the GMAT Prep test and I can't figure out the solution for the following question:

In a Pet-Shop 1/3 of the pets are dogs and 1/5 of the pets are birds. How many of the dogs are pets?
(1) There are 30 birds in the Pet-Shop
(2) There are 20 more Birds than dogs in the Pet-Shop

The correct answer is D - Both statements seperately are sufficient.
(1) is clear to me - but I'm struggling to see how (2) is sufficient to identify the number of dogs.

Do you guys have an idea?

Cheers
Thomas
It shld have been other way round There are 20 more Dogs than birds
Top
Post new topic Post Reply
• Page 1 of 1