Find all School-related info fast with the new School-Specific MBA Forum

It is currently 27 Aug 2015, 22:16
GMAT Club Tests

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.

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

A tank contains 10,000 gallons of a solution that is 5 %

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
Manager
Manager
avatar
Joined: 04 Oct 2005
Posts: 246
Followers: 1

Kudos [?]: 24 [0], given: 0

A tank contains 10,000 gallons of a solution that is 5 % [#permalink] New post 11 Oct 2005, 02:04
2
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

  15% (low)

Question Stats:

74% (02:03) correct 26% (01:15) wrong based on 303 sessions
A tank contains 10,000 gallons of a solution that is 5 percent sodium chloride by volume. If 2,500 gallons of water evaporate from the tank, the remaining solution will be approximately what percent sodium chloride?

(A) 1.25%
(B) 3.75%
(C) 6.25%
(D) 6.67%
(E) 11.7%
[Reveal] Spoiler: OA
2 KUDOS received
Senior Manager
Senior Manager
avatar
Joined: 11 May 2004
Posts: 458
Location: New York
Followers: 1

Kudos [?]: 18 [2] , given: 0

Re: PS - Percents OG11 [#permalink] New post 11 Oct 2005, 14:23
2
This post received
KUDOS
Should be D

Original =10,000 ----> sodium chloride = 5% ie 500
New = 10,000-2,500 = 7500.

New % = (500/7500) * 100

= 6.67%

nero44 wrote:
I think my brain evaporated, because I dont even get any of the solutions given...

A tank contains 10,000 gallons of a solution that is 5 percent sodium chloride by volume. If 2,500 gallons of water evaporate from the tank, the remaining solution will be approximately what percent sodium chloride?

(A) 1.25%
(B) 3.75%
(C) 6.25%
(D) 6.67%
(E) 11.7%
1 KUDOS received
SVP
SVP
avatar
Joined: 14 Dec 2004
Posts: 1706
Followers: 1

Kudos [?]: 66 [1] , given: 0

 [#permalink] New post 11 Oct 2005, 02:54
1
This post received
KUDOS
I got 6.67%


10000 gallons solution has
500 gallons sodium chloride
9500 gallons water


=> 2500 gallons water evaporates
=> 7000 gallons water remains

hence, concentration of sodium chloride is 500/7500 = 6.67%
Expert Post
1 KUDOS received
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 29090
Followers: 4720

Kudos [?]: 49587 [1] , given: 7395

Re: A tank contains 10,000 gallons of a solution that is 5% [#permalink] New post 03 Mar 2012, 15:45
1
This post received
KUDOS
Expert's post
Minhphuoc wrote:
A tank contains 10,000 gallons of a solution that is 5 percent sodium chloride by volume. If 2,500 gallons of water evaporate from the tank, the remaining solution will be approximately what percent sodium chloride?

(A) 1.25%
(B) 3.75%
(C) 6.25%
(D) 6.67%
(E) 11.7%

hi, everybody,

Sorry for raised this question again, but I a little bit confused with the question by itself.

Is that correct that if I interpret the question statement 'the remaining solution' (A) will be approximately what percent (B) 'sodium chloride'? as A=%B?

It makes me generate wrong answer!

Thanks


"The remaining solution will be approximately what percent sodium chloride?" means: what percent of the remaining solution is sodium chloride. Now, since the remaining solution is 10,000-2,500=7,500 gallons and sodium chloride is 500 gallons (5% of initial solution of 10,000 gallons) then sodium chloride is 500/7,500*100=~6.66% of the remaining solution of 7,500 gallons.

Answer: D.

Hope it's clear.
_________________

NEW TO MATH FORUM? PLEASE READ THIS: ALL YOU NEED FOR QUANT!!!

PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

RESOURCES: [GMAT MATH BOOK]; 1. Triangles; 2. Polygons; 3. Coordinate Geometry; 4. Factorials; 5. Circles; 6. Number Theory; 7. Remainders; 8. Overlapping Sets; 9. PDF of Math Book; 10. Remainders; 11. GMAT Prep Software Analysis ; 12. SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) ; 12. 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?
25 extra-hard Quant Tests

GMAT Club Premium Membership - big benefits and savings

Expert Post
1 KUDOS received
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 29090
Followers: 4720

Kudos [?]: 49587 [1] , given: 7395

Re: A tank contains 10,000 gallons of a solution that is 5 % [#permalink] New post 20 Jan 2015, 02:18
1
This post received
KUDOS
Expert's post
arshu27 wrote:
Bunuel wrote:
Minhphuoc wrote:
A tank contains 10,000 gallons of a solution that is 5 percent sodium chloride by volume. If 2,500 gallons of water evaporate from the tank, the remaining solution will be approximately what percent sodium chloride?

(A) 1.25%
(B) 3.75%
(C) 6.25%
(D) 6.67%
(E) 11.7%

hi, everybody,

Sorry for raised this question again, but I a little bit confused with the question by itself.

Is that correct that if I interpret the question statement 'the remaining solution' (A) will be approximately what percent (B) 'sodium chloride'? as A=%B?





It makes me generate wrong answer!

Thanks


"The remaining solution will be approximately what percent sodium chloride?" means: what percent of the remaining solution is sodium chloride. Now, since the remaining solution is 10,000-2,500=7,500 gallons and sodium chloride is 500 gallons (5% of initial solution of 10,000 gallons) then sodium chloride is 500/7,500*100=~6.66% of the remaining solution of 7,500 gallons.

Answer: D.

Hope it's clear.




Hi Bunuel,

As you said the question asks 'what percent of the remaining solution is sodium chloride'.

After evaporation,

volume of water=7500 gallons

volume of sodium chloride =500(no change)

total volume of the SOLUTION(water and sodium chloride)=7500+500

therfore 500/8000*100=6.25

Even though this does not match the right answer my doubt is why are you not taking the total which includes both? Initially we did take solution to be water and sodium chloride as one.The question uses the term 'remaining solution'. Could you please help me clear this confusion?


After 2,500 gallons of water evaporates from the tank, we are left with 7,500 gallons of solution, which includes 500 gallons of sodium chloride.
_________________

NEW TO MATH FORUM? PLEASE READ THIS: ALL YOU NEED FOR QUANT!!!

PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

RESOURCES: [GMAT MATH BOOK]; 1. Triangles; 2. Polygons; 3. Coordinate Geometry; 4. Factorials; 5. Circles; 6. Number Theory; 7. Remainders; 8. Overlapping Sets; 9. PDF of Math Book; 10. Remainders; 11. GMAT Prep Software Analysis ; 12. SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) ; 12. 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?
25 extra-hard Quant Tests

GMAT Club Premium Membership - big benefits and savings

SVP
SVP
User avatar
Joined: 24 Sep 2005
Posts: 1891
Followers: 13

Kudos [?]: 173 [0], given: 0

Re: PS - Percents OG11 [#permalink] New post 11 Oct 2005, 02:48
nero44 wrote:
I think my brain evaporated, because I dont even get any of the solutions given...

A tank contains 10,000 gallons of a solution that is 5 percent sodium chloride by volume. If 2,500 gallons of water evaporate from the tank, the remaining solution will be approximately what percent sodium chloride?

(A) 1.25%
(B) 3.75%
(C) 6.25%
(D) 6.67%
(E) 11.7%


there're 5%*10,000(= 500 gallons) of NaCl in the solution
===> there're 9,500 (=10,000-500) gallons of water in the solution.
after 2,500 gallons of water evaporate, there's 7,000 gallons of water left ===> the percentage of NaCl is 500 gallons NaCl/ (500+7,000) ( this is the volume of the solution) *100%= 6,67% . It's D.
Intern
Intern
avatar
Joined: 16 Nov 2009
Posts: 7
Followers: 0

Kudos [?]: 0 [0], given: 0

Re: A tank contains 10,000 gallons of a solution that is 5% [#permalink] New post 03 Mar 2012, 10:14
hi, everybody,

Sorry for raised this question again, but I a little bit confused with the question by itself.

Is that correct that if I interpret the question statement 'the remaining solution' (A) will be approximately what percent (B) 'sodium chloride'? as A=%B?

It makes me generate wrong answer!

Thanks
Intern
Intern
avatar
Joined: 19 Mar 2012
Posts: 10
Followers: 0

Kudos [?]: 2 [0], given: 0

Re: A tank contains 10,000 gallons of a solution that is 5 % [#permalink] New post 27 Mar 2012, 21:30
I'm really slow with math, need suggestions.

I solved this question in 2 minutes 45 seconds and got the correct answer, but obviously my time was too slow. Any suggestions for how to complete this quickly? The slowest part for me was calculating what 500/7500 is.

This was my process:
500/7500 = 5/75 = 1/15.

Long division 1/15 = 6.6% (then looked for correct answer).

Any suggestions for how to do that calculation faster (beyond just memorizing) would be great!
GMAT Club Legend
GMAT Club Legend
User avatar
Joined: 09 Sep 2013
Posts: 6079
Followers: 340

Kudos [?]: 68 [0], given: 0

Premium Member
Re: A tank contains 10,000 gallons of a solution that is 5 % [#permalink] New post 02 Oct 2013, 13:33
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.
_________________

GMAT Books | GMAT Club Tests | Best Prices on GMAT Courses | GMAT Mobile App | Math Resources | Verbal Resources

Manager
Manager
User avatar
Status: folding sleeves up
Joined: 26 Apr 2013
Posts: 105
Location: India
Concentration: Finance, Strategy
GMAT Date: 10-31-2014
GPA: 3.5
WE: Consulting (Computer Hardware)
Followers: 1

Kudos [?]: 18 [0], given: 38

Re: A tank contains 10,000 gallons of a solution that is 5 % [#permalink] New post 12 Oct 2013, 01:50
Image
Senior Manager
Senior Manager
User avatar
Status: Math is psycho-logical
Joined: 07 Apr 2014
Posts: 447
Location: Netherlands
GMAT Date: 02-11-2015
WE: Psychology and Counseling (Other)
Followers: 1

Kudos [?]: 59 [0], given: 169

A tank contains 10,000 gallons of a solution that is 5 % [#permalink] New post 19 Jan 2015, 08:49
Hey,

I have two questions on this problem:
1) Saying that it is a "solution" we should assume that there are at least 2 elements in it?
2) Because it says 2500 gallons of water evaporated, we should assume that only water evaporated, so the sodium chloride has remained intact?

That because if you think that the solution is the "sodium chloride", then the % should remain the same (5%) after some amount of the solution is gone. Which would make you answer # B. Even though this is obiously wrong as the % would be the same..

It does make sense that you are supposed to understand that there are 2 elements in this solution, and sodium chloride has remained intact, since it was only water that evaporated, but I guess in this case they could have made it a bit more obvious by saying "If 2,500 gallons that consist only of water evaporate from the tank ", then you would get the correct answer quite easily...

Sorry, it just seems a bit ridiculous that they trick you for silly reasons..
Intern
Intern
avatar
Joined: 25 Jan 2014
Posts: 17
Concentration: Technology, General Management
Followers: 0

Kudos [?]: 0 [0], given: 74

Re: A tank contains 10,000 gallons of a solution that is 5 % [#permalink] New post 19 Jan 2015, 09:40
Bunuel wrote:
Minhphuoc wrote:
A tank contains 10,000 gallons of a solution that is 5 percent sodium chloride by volume. If 2,500 gallons of water evaporate from the tank, the remaining solution will be approximately what percent sodium chloride?

(A) 1.25%
(B) 3.75%
(C) 6.25%
(D) 6.67%
(E) 11.7%

hi, everybody,

Sorry for raised this question again, but I a little bit confused with the question by itself.

Is that correct that if I interpret the question statement 'the remaining solution' (A) will be approximately what percent (B) 'sodium chloride'? as A=%B?





It makes me generate wrong answer!

Thanks


"The remaining solution will be approximately what percent sodium chloride?" means: what percent of the remaining solution is sodium chloride. Now, since the remaining solution is 10,000-2,500=7,500 gallons and sodium chloride is 500 gallons (5% of initial solution of 10,000 gallons) then sodium chloride is 500/7,500*100=~6.66% of the remaining solution of 7,500 gallons.

Answer: D.

Hope it's clear.




Hi Bunuel,

As you said the question asks 'what percent of the remaining solution is sodium chloride'.

After evaporation,

volume of water=7500 gallons

volume of sodium chloride =500(no change)

total volume of the SOLUTION(water and sodium chloride)=7500+500

therfore 500/8000*100=6.25

Even though this does not match the right answer my doubt is why are you not taking the total which includes both? Initially we did take solution to be water and sodium chloride as one.The question uses the term 'remaining solution'. Could you please help me clear this confusion?
Intern
Intern
avatar
Joined: 25 Jan 2014
Posts: 17
Concentration: Technology, General Management
Followers: 0

Kudos [?]: 0 [0], given: 74

Re: A tank contains 10,000 gallons of a solution that is 5 % [#permalink] New post 21 Jan 2015, 12:15
thank you Bunuel. got it!
Intern
Intern
avatar
Joined: 10 Dec 2012
Posts: 34
Followers: 0

Kudos [?]: 1 [0], given: 19

Re: A tank contains 10,000 gallons of a solution that is 5 % [#permalink] New post 22 Jul 2015, 20:27
nero44 wrote:
A tank contains 10,000 gallons of a solution that is 5 percent sodium chloride by volume. If 2,500 gallons of water evaporate from the tank, the remaining solution will be approximately what percent sodium chloride?

(A) 1.25%
(B) 3.75%
(C) 6.25%
(D) 6.67%
(E) 11.7%



I got confused with this question,i thought when water would evaporate so would sodium chloride, and if 2500 solution evaporates , then there would be some kind of proportion by which evaporation happens--eg 500:9500 , so i applied all the logic and then read the question and explanation...there was i Wrong :)...Gmat can be very frustrating at time,,but fun too
Re: A tank contains 10,000 gallons of a solution that is 5 %   [#permalink] 22 Jul 2015, 20:27
    Similar topics Author Replies Last post
Similar
Topics:
10 Experts publish their posts in the topic A tank contains 10,000 gallons of a solution that is 5 Walkabout 12 20 Dec 2012, 05:23
A tank contains GMATD11 3 13 Feb 2011, 02:03
44 Experts publish their posts in the topic Tanks X and Y contain 500 and 200 gallons of water respectiv ichha148 20 26 Sep 2010, 19:04
If Henry were to add 5 gallons of water to a tank that is Jcpenny 2 05 Nov 2008, 15:26
7 Experts publish their posts in the topic A tank holds x gallons of a saltwater solution that is 20% Manbehindthecurtain 9 22 Feb 2008, 15:33
Display posts from previous: Sort by

A tank contains 10,000 gallons of a solution that is 5 %

  Question banks Downloads My Bookmarks Reviews Important topics  


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

Powered by phpBB © phpBB Group and phpBB SEO

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®.