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

It is currently 10 Dec 2018, 23:19

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
Events & Promotions in December
PrevNext
SuMoTuWeThFrSa
2526272829301
2345678
9101112131415
16171819202122
23242526272829
303112345
Open Detailed Calendar
  • Free GMAT Prep Hour

     December 11, 2018

     December 11, 2018

     09:00 PM EST

     10:00 PM EST

    Strategies and techniques for approaching featured GMAT topics. December 11 at 9 PM EST.
  • Free lesson on number properties

     December 10, 2018

     December 10, 2018

     10:00 PM PST

     11:00 PM PST

    Practice the one most important Quant section - Integer properties, and rapidly improve your skills.

The 15 homes in a new development are each to be sold for

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

Hide Tags

Intern
Intern
avatar
Joined: 26 Oct 2012
Posts: 1
The 15 homes in a new development are each to be sold for  [#permalink]

Show Tags

New post Updated on: 09 Nov 2012, 01:46
4
00:00
A
B
C
D
E

Difficulty:

  5% (low)

Question Stats:

91% (01:56) correct 9% (02:27) wrong based on 244 sessions

HideShow timer Statistics

The 15 homes in a new development are each to be sold for one of three different prices so that the developer receives an average (arithmetic mean) of $200,000 per home. If 4 of the homes are to be sold for $170,000 each and 5 are to be sold for $200,000 each, what will be the selling price of each of the remaining 6 homes?

A. $200,000
B. $210,000
C. $215,000
D. $220,000
E. $230,000

Originally posted by bssys on 08 Nov 2012, 12:36.
Last edited by Bunuel on 09 Nov 2012, 01:46, edited 1 time in total.
Renamed the topic and edited the question.
Most Helpful Expert Reply
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 51075
Re: The 15 homes in a new development are each to be sold for  [#permalink]

Show Tags

New post 09 Nov 2012, 01:54
4
3
bssys wrote:
The 15 homes in a new development are each to be sold for one of three different prices so that the developer receives an average (arithmetic mean) of $200,000 per home. If 4 of the homes are to be sold for $170,000 each and 5 are to be sold for $200,000 each, what will be the selling price of each of the remaining 6 homes?

A. $200,000
B. $210,000
C. $215,000
D. $220,000
E. $230,000


Since the average price of 15 of the homes is $200, then the total price of these homes is 15*$200=$3,000.

The total price of 4 of the homes is 4*$170=$680;
The total price of 5 of the homes is 5*$200=$1,000;

Therefore the total price of the remaining 6 of the homes is $3,000-($680+$1,000)=$1,320. The average price per home is $1,320/6=$220.

Answer: D.

Hope it's clear.
_________________

New to the Math Forum?
Please read this: Ultimate GMAT Quantitative Megathread | All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics

General Discussion
Board of Directors
User avatar
P
Joined: 01 Sep 2010
Posts: 3294
Re: PS GMAT PREP Quest.  [#permalink]

Show Tags

New post 08 Nov 2012, 13:09
1
This is a classic problem that during your gmat exam makes you out of balance, nervous because you deal with a lot of information.

Ok take control of the question. (I have structured my answer step by step, like a process of thoughts)

First of all we have 15 homes so odd number.

Second this 15 is grouped in 3 blocks or groups whatever you want to say.

Now is the best part: one group is 170 of 4 this is important to take in account the other 5 (strees on this) 200

Now look at the answer choices : A is not possible. out

Now is the moment to attack the question. The best strategy here is a weighted average strategy.

considering the average is more or less in the middle, it follows that the group of 6 is what we are looking for and is between 170 and 200 or after 200. We have 170 200 and 6*x and the average is 200: in some place we have to put 6*x

Now in the average what value has a major "weight" No the group pf 4 with 170 ( value 680) but the 5 houses with 200 (value 1000).

So the average tends to the latter or is after, otherwise we do not have 200 like average. In this kind of problem the last value (in increasing order as we can see) is never the answer because put our value to close at the end point of our weighted average.

So the answer must be D

I hope my explanation is useful
_________________

COLLECTION OF QUESTIONS AND RESOURCES
Quant: 1. ALL GMATPrep questions Quant/Verbal 2. Bunuel Signature Collection - The Next Generation 3. Bunuel Signature Collection ALL-IN-ONE WITH SOLUTIONS 4. Veritas Prep Blog PDF Version 5. MGMAT Study Hall Thursdays with Ron Quant Videos
Verbal:1. Verbal question bank and directories by Carcass 2. MGMAT Study Hall Thursdays with Ron Verbal Videos 3. Critical Reasoning_Oldy but goldy question banks 4. Sentence Correction_Oldy but goldy question banks 5. Reading-comprehension_Oldy but goldy question banks

Board of Directors
User avatar
P
Joined: 01 Sep 2010
Posts: 3294
Re: PS GMAT PREP Quest.  [#permalink]

Show Tags

New post 08 Nov 2012, 16:22
Intern
Intern
avatar
Joined: 27 Feb 2012
Posts: 37
The 15 homes in a new development are each to be sold for  [#permalink]

Show Tags

New post 19 Jan 2013, 23:24
The 15 homes in a new development are each to be sold for one of three different prices so that the developer receives an average (arithmetic mean) of $200,000 per home. If 4 of the homes are to be sold for $170,000 each and 5 are to be sold for $200,000 each, what will be the selling price of each of the remaining 6 homes?

A) $200,000
B) $210,000
C) $215,000
D) $220,000
E) $230,000


This was taken from GMAT prep test, but i didnt know that when you exit out you can not review the correct answers for the test.
VP
VP
User avatar
Status: Been a long time guys...
Joined: 03 Feb 2011
Posts: 1134
Location: United States (NY)
Concentration: Finance, Marketing
GPA: 3.75
GMAT ToolKit User Premium Member
Re: The 15 homes in a new development are each to be sold for  [#permalink]

Show Tags

New post 20 Jan 2013, 00:13
2
jsphcal wrote:
The 15 homes in a new development are each to be sold for one of three different prices so that the developer receives an average (arithmetic mean) of $200,000 per home. If 4 of the homes are to be sold for $170,000 each and 5 are to be sold for $200,000 each, what will be the selling price of each of the remaining 6 homes?

A) $200,000
B) $210,000
C) $215,000
D) $220,000
E) $230,000


This was taken from GMAT prep test, but i didnt know that when you exit out you can not review the correct answers for the test.

IMO the answer has to be D.
5 houses are being sold for 200,000. 4 houses are being sold for $30,000 less, resulting in a loss of $120,000. To make the average selling price intact i.e. $200,000, the remaining 6 houses must be sold at such a profit that it compensates for the loss of 120,000. Hence 6x=120,000.
x=20,000.
The 6 houses are sold at $20,000 profit or at $220,000.
+1D
_________________

Prepositional Phrases Clarified|Elimination of BEING| Absolute Phrases Clarified
Rules For Posting
www.Univ-Scholarships.com

Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 51075
Re: The 15 homes in a new development are each to be sold for  [#permalink]

Show Tags

New post 20 Jan 2013, 03:52
jsphcal wrote:
The 15 homes in a new development are each to be sold for one of three different prices so that the developer receives an average (arithmetic mean) of $200,000 per home. If 4 of the homes are to be sold for $170,000 each and 5 are to be sold for $200,000 each, what will be the selling price of each of the remaining 6 homes?

A) $200,000
B) $210,000
C) $215,000
D) $220,000
E) $230,000


This was taken from GMAT prep test, but i didnt know that when you exit out you can not review the correct answers for the test.


Merging similar topics. Please refer to the solutions above.
_________________

New to the Math Forum?
Please read this: Ultimate GMAT Quantitative Megathread | All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics

Manager
Manager
User avatar
Status: Please do not forget to give kudos if you like my post
Joined: 19 Sep 2008
Posts: 94
Location: United States (CA)
GMAT ToolKit User Premium Member
Re: The 15 homes in a new development are each to be sold for  [#permalink]

Show Tags

New post 09 Dec 2014, 18:04
Fastest way to do the calculation is as shown below:
Avg = 200
so lets find the deviation from avg for each sale.

i.e for 4 homes its was -30, 5 homes it was 0 and let x be deviation for rest of the 6 homes.

setup a equation: -30*4 + 5*0 + x*6 = 0 <== (basically 0*15) find x = 20 so the homes should be sold for 220,000 of avg to converge to 200,000.

Answer: D


bssys wrote:
The 15 homes in a new development are each to be sold for one of three different prices so that the developer receives an average (arithmetic mean) of $200,000 per home. If 4 of the homes are to be sold for $170,000 each and 5 are to be sold for $200,000 each, what will be the selling price of each of the remaining 6 homes?

A. $200,000
B. $210,000
C. $215,000
D. $220,000
E. $230,000

_________________

Please Help with Kudos, if you like my post.


SVP
SVP
User avatar
Status: The Best Or Nothing
Joined: 27 Dec 2012
Posts: 1826
Location: India
Concentration: General Management, Technology
WE: Information Technology (Computer Software)
Re: The 15 homes in a new development are each to be sold for  [#permalink]

Show Tags

New post 10 Dec 2014, 19:32
1
1
For the sake of calculation, remove the 3 extra zero's from the question as well as answer

\(Answer = \frac{200*15 - 170*4 - 200*5}{6} = \frac{3000 - 1680}{6} = 500 - 280 = 220\)

Answer = D = 220000
_________________

Kindly press "+1 Kudos" to appreciate :)

Senior Manager
Senior Manager
User avatar
Status: Math is psycho-logical
Joined: 07 Apr 2014
Posts: 419
Location: Netherlands
GMAT Date: 02-11-2015
WE: Psychology and Counseling (Other)
Re: The 15 homes in a new development are each to be sold for  [#permalink]

Show Tags

New post 06 Jan 2015, 01:53
I also used Paresh's approach - weighted average.

I only wanted to add that it helps to map out the information we have, after we write down the formula for the mean.

M=S/N
Then, looking into the text, we know:
M=200.000
N=15 houses
S= M*N= 3.000.000 total amount of money earned by selling all 15 houses.

This 3.000.000 is comprised of houses sold at a different price, so this is where the concept of the weighted average is used.

4 houses were sold for 170.000
5 houses were sold for 200.000
6 houses were sold for X
---------------------------------
15 houses were sold for 370.000 + X

Using the formula for the mean:
M=S/N
200.000 = (4*170.000 + 5*200.000 + 6*X) / 15
200.000*15 = 1.680.000 + 6X
3.000.000-1.680.000 = 6X
1.320.000 / 6 = X
220.000 = X ANS D
Target Test Prep Representative
User avatar
G
Status: Head GMAT Instructor
Affiliations: Target Test Prep
Joined: 04 Mar 2011
Posts: 2830
Re: The 15 homes in a new development are each to be sold for  [#permalink]

Show Tags

New post 05 Apr 2018, 15:56
bssys wrote:
The 15 homes in a new development are each to be sold for one of three different prices so that the developer receives an average (arithmetic mean) of $200,000 per home. If 4 of the homes are to be sold for $170,000 each and 5 are to be sold for $200,000 each, what will be the selling price of each of the remaining 6 homes?

A. $200,000
B. $210,000
C. $215,000
D. $220,000
E. $230,000


The total selling price of the 4 homes is 4 x 170,000 = $680,000, and the total selling price of the 5 homes is 200,000 x 5 = $1,000,000. Thus, the total selling price of these 9 homes is $1,680,000.

The total selling of the all 15 homes is 15 x 200,000 = $3,000,000.

Thus, the total selling price of the remaining 6 homes is 3,000,000 - 1,680,000 = $1,320,000, resulting in a price of 1,320,000/6 = $220,000 per home.

Answer: D
_________________

Jeffery Miller
Head of GMAT Instruction

GMAT Quant Self-Study Course
500+ lessons 3000+ practice problems 800+ HD solutions

Manager
Manager
User avatar
G
Joined: 10 Apr 2018
Posts: 180
Re: The 15 homes in a new development are each to be sold for  [#permalink]

Show Tags

New post 17 Aug 2018, 11:48
Hello,

Such questions can be answered in 30 -45 secs if we master the deviation principle

Assume that average price of each of 6 houses sold is 200,000.
and 4 houses were sold at less than average by 30,000 each= 30000*4=120,000
Now this price of 120,000 must be equally added to the price of each 6 houses to maintain the avg at 200,000
so
200,000+(120,000/6)= 220,000

Probus
GMAT Club Bot
Re: The 15 homes in a new development are each to be sold for &nbs [#permalink] 17 Aug 2018, 11:48
Display posts from previous: Sort by

The 15 homes in a new development are each to be sold for

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


Copyright

GMAT Club MBA Forum Home| About| Terms and Conditions and Privacy Policy| GMAT Club Rules| Contact| Sitemap

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®.