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 →

Nice DS Question

Expert replies
Post new topic Post Reply
Previous Topic Next Topic
User avatar
Legendary Member
Posts: 1556
Joined: Tue Aug 14, 2012 11:18 pmFollowed by: 34 members
Thanked: 448 times
GMAT Score:650
by theCodeToGMAT » Wed Sep 18, 2013 11:34 pm
In Greenville last July, what was the average (arithmetic mean) home sale price?

(1) In Greenville last July, there were 100 homes sold for a total of $51 million.

(2) In Greenville last July, condominiums accounted for 60% of the home sales, and the average
condominium price was $450,000.

OA After some replies
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Source: — Data Sufficiency |
Newbie | Next Rank: 10 Posts
Posts: 4
Joined: Tue Mar 19, 2013 3:09 pm

by bigb62387 » Thu Sep 19, 2013 5:29 am
Can't be anything other than A, right?

(1) Average = Sum / N

Sum = $51 million
N = 100
SUFFICIENT

(2) 60% sold at $450,000, but we're told nothing about the remaining 40%. They could have been sold for $1 a piece or $1 million a piece, and we would end up with 2 very different averages.
INSUFFICIENT
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
User avatar
Legendary Member
Posts: 1556
Joined: Tue Aug 14, 2012 11:18 pmFollowed by: 34 members
Thanked: 448 times
GMAT Score:650

by theCodeToGMAT » Thu Sep 19, 2013 6:25 am
bigb62387 wrote:Can't be anything other than A, right?

(1) Average = Sum / N

Sum = $51 million
N = 100
SUFFICIENT

(2) 60% sold at $450,000, but we're told nothing about the remaining 40%. They could have been sold for $1 a piece or $1 million a piece, and we would end up with 2 very different averages.
INSUFFICIENT
Yes, it is other than [spoiler][A] [/spoiler]
R A H U L
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

by Brent@GMATPrepNow » Thu Sep 19, 2013 6:53 am
theCodeToGMAT wrote:In Greenville last July, what was the average (arithmetic mean) home sale price?

(1) In Greenville last July, there were 100 homes sold for a total of $51 million.

(2) In Greenville last July, condominiums accounted for 60% of the home sales, and the average condominium price was $450,000.
I'm not sure how the answer isn't A

My full solution . . .

Target question: What was the average home sale price last July?

Statement 1: In Greenville last July, there were 100 homes sold for a total of $51 million.
Average home sale price = (sum of all sales)/(# of sales)
= $51,000,000/100
= $510,000
Since we can answer the target question with certainty, statement 1 is SUFFICIENT

Statement 2: In Greenville last July, condominiums accounted for 60% of the home sales, and the average condominium price was $450,000.
There are several possible cases that satisfy this condition. Here are two:
Case a: There were 5 home sales last July. 3 condos sold for $450,000 each, and 2 houses sold for $10 billion each. In this case, the average sale price is over $4 billion
Case b: There were 5 home sales last July. 3 condos sold for $450,000 each, and 2 houses sold for $1 each. In this case, the average sale price is less than $200,000
Since we cannot answer the target question with certainty, statement 2 is NOT SUFFICIENT

Answer = A

What the source of this question?

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
Legendary Member
Posts: 1556
Joined: Tue Aug 14, 2012 11:18 pmFollowed by: 34 members
Thanked: 448 times
GMAT Score:650

by theCodeToGMAT » Thu Sep 19, 2013 7:49 am
Brent@GMATPrepNow wrote:
theCodeToGMAT wrote:In Greenville last July, what was the average (arithmetic mean) home sale price?

(1) In Greenville last July, there were 100 homes sold for a total of $51 million.

(2) In Greenville last July, condominiums accounted for 60% of the home sales, and the average condominium price was $450,000.
I'm not sure how the answer isn't A

My full solution . . .

Target question: What was the average home sale price last July?

Statement 1: In Greenville last July, there were 100 homes sold for a total of $51 million.
Average home sale price = (sum of all sales)/(# of sales)
= $51,000,000/100
= $510,000
Since we can answer the target question with certainty, statement 1 is SUFFICIENT

Statement 2: In Greenville last July, condominiums accounted for 60% of the home sales, and the average condominium price was $450,000.
There are several possible cases that satisfy this condition. Here are two:
Case a: There were 5 home sales last July. 3 condos sold for $450,000 each, and 2 houses sold for $10 billion each. In this case, the average sale price is over $4 billion
Case b: There were 5 home sales last July. 3 condos sold for $450,000 each, and 2 houses sold for $1 each. In this case, the average sale price is less than $200,000
Since we cannot answer the target question with certainty, statement 2 is NOT SUFFICIENT

Answer = A

What the source of this question?

Cheers,
Brent
Brent, even I was quite satisfied that the Answer cannot be other than [A]. However, the explanation is also satisfying, making me feel that I was wrong.
According to the explanation, the Question Stem is seeking the Average price of HOME SALE PRICE. And, the Statement 1 describes the Average price of 100 Homes. So, explanation concludes that since we are provided the details of only 100 homes, we cannot extrapolate to give details of all home.
R A H U L
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

by Brent@GMATPrepNow » Thu Sep 19, 2013 8:02 am
theCodeToGMAT wrote: Brent, even I was quite satisfied that the Answer cannot be other than [A]. However, the explanation is also satisfying, making me feel that I was wrong.
According to the explanation, the Question Stem is seeking the Average price of HOME SALE PRICE. And, the Statement 1 describes the Average price of 100 Homes. So, explanation concludes that since we are provided the details of only 100 homes, we cannot extrapolate to give details of all home.
Hmmmmmmmmmmmmmmmmmmmmmmmm.
So, "there were 100 homes sold" does not mean that 100 homes sold? It means that more than 100 homes were sold?
I'm quite certain that the GMAT would not use such ambiguous wording. For example, if a GMAT question states that "Joe owns 3 cars," this does not mean that Joe might own more than 3 cars.

What's the source of this question?

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
Legendary Member
Posts: 1556
Joined: Tue Aug 14, 2012 11:18 pmFollowed by: 34 members
Thanked: 448 times
GMAT Score:650

by theCodeToGMAT » Thu Sep 19, 2013 9:52 am
Brent@GMATPrepNow wrote:
theCodeToGMAT wrote: Brent, even I was quite satisfied that the Answer cannot be other than [A]. However, the explanation is also satisfying, making me feel that I was wrong.
According to the explanation, the Question Stem is seeking the Average price of HOME SALE PRICE. And, the Statement 1 describes the Average price of 100 Homes. So, explanation concludes that since we are provided the details of only 100 homes, we cannot extrapolate to give details of all home.
Hmmmmmmmmmmmmmmmmmmmmmmmm.
So, "there were 100 homes sold" does not mean that 100 homes sold? It means that more than 100 homes were sold?
I'm quite certain that the GMAT would not use such ambiguous wording. For example, if a GMAT question states that "Joe owns 3 cars," this does not mean that Joe might own more than 3 cars.

What's the source of this question?

Cheers,
Brent
Not sure of the Source.. I am solving some PDFs which contain random questions..

However, this question is old.. I searched and found that similar post was raised a year back on some other gmat forum. The person who posted the question wrote "I have two documents. Both have different answers. Please explain." for Answer :P
R A H U L
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Post new topic Post Reply
• Page 1 of 1