GMAT Question of the Day: Daily via email | Daily via Instagram New to GMAT Club? Watch this Video

It is currently 22 Feb 2020, 22:11

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

Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram

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

Hide Tags

Find Similar Topics 
Intern
Intern
avatar
Joined: 19 Dec 2009
Posts: 25
Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram  [#permalink]

Show Tags

New post 08 Nov 2010, 13:02
2
1
42
00:00
A
B
C
D
E

Difficulty:

  45% (medium)

Question Stats:

71% (02:41) correct 29% (02:44) wrong based on 708 sessions

HideShow timer Statistics

Solution Y is 30 percent liquid X and 70 percent water. If 2 kilograms of water evaporate from 8 kilograms of solutions Y and 2 kilograms of solution Y are added to the remaining 6 kilograms of liquid, what percent of this new liquid solution is liquid X?

A. 30%
B. 33 1/3%
C. 37 1/2%
D. 40%
E. 50%

Project PS Butler : Question #106


Subscribe to get Daily Email - Click Here | Subscribe via RSS - RSS
Most Helpful Expert Reply
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 61396
Re: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram  [#permalink]

Show Tags

New post 06 Apr 2012, 12:19
5
7
rovshan85 wrote:
Solution Y is 30% liquid X and 70 percent water. If 2 kilograms of water evaporate from 8 kg of solution Y and 2 kg of solution Y are added to the remaining 6 kg of liquid, what percent of this new solution is liquid X?

a. 30
b. 33 1/3
c. 37 1/2
d. 40
e. 50

What is the easiest way to approach this type of problem and solve under 2 min.


In 8 kilograms of solution Y there are 0.3*8=2.4 kilograms of solution X;

After 2 kilograms of water are replaced by 2 kilograms of solution Y, to the existing 2.4 kilograms of solution X, 0.3*2=0.6 kilograms of solution X are added, so in the new solution of 8 kilograms there are 2.4+0.6=3 kilograms of solution X, which is 3/8*100=37.5% of this new solution.

Answer: C.
_________________
Most Helpful Community Reply
Intern
Intern
avatar
Joined: 24 Aug 2010
Posts: 5
Re: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram  [#permalink]

Show Tags

New post 08 Nov 2010, 13:16
3
3
At the beggining, you have 8KG of solution Y, i.e.

70% * 8KG = 5,6 KG of Water
30% * 8KG = 2,4 KG of X

2KG of water evaporate:

5,6KG - 2KG = 3,6KG of Water
2,4KG of X

2KG of liquid are added:

3,6KG + 2*0,70 = 5KG of Water
2,4KG + 2*0,30 = 3 KG of X

So you have 3KG of X in 8KG (3 + 5) solution.
Therefore X concentration is 3/8 = 37,5%
General Discussion
Manager
Manager
User avatar
Status: Not afraid of failures, disappointments, and falls.
Joined: 20 Jan 2010
Posts: 243
Concentration: Technology, Entrepreneurship
WE: Operations (Telecommunications)
GMAT ToolKit User
Re: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram  [#permalink]

Show Tags

New post 08 Nov 2010, 23:01
1
Answer:C
Took time to solve this one, the statement 2 kilograms of solution Y are added to the remaining 6 kilograms of liquid was confusing to me. After thinking more deeply, it was clear to me that new 2 kg of solution Y will also be 30% liquid X and 70% water, and then I was able to get the answer. That was a bit tricky and nice question.
Kudos +1 for posting the question :)
Retired Moderator
User avatar
Joined: 02 Sep 2010
Posts: 709
Location: London
GMAT ToolKit User Reviews Badge
Re: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram  [#permalink]

Show Tags

New post 08 Nov 2010, 23:25
2
Initially you start with 8kg of solution which has 2.4kg of X and 5.6kg of water
Post evaporation : 2.4kg of X and 3.6kg of water
Now we add back 2kg of Y --> 1.4Kg water + 0.6Kg X
So we have left 5Kg Water & 3Kg X

Percentage concentration is (3/5)*100 or 37.5%
_________________
Manager
Manager
User avatar
Status: Not afraid of failures, disappointments, and falls.
Joined: 20 Jan 2010
Posts: 243
Concentration: Technology, Entrepreneurship
WE: Operations (Telecommunications)
GMAT ToolKit User
Re: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram  [#permalink]

Show Tags

New post 08 Nov 2010, 23:43
shrouded1 wrote:
Initially you start with 8kg of solution which has 2.4kg of X and 5.6kg of water
Post evaporation : 2.4kg of X and 3.6kg of water
Now we add back 2kg of Y --> 1.4Kg water + 0.6Kg X
So we have left 5Kg Water & 3Kg X

Percentage concentration is (3/5)*100 or 37.5%

Yea, that's exactly how I solved but you know at first I was kinda adding 2 to 6 kg without considering liquid X and water's concentration within 2 kg being added.
Senior Manager
Senior Manager
User avatar
S
Status: No dream is too large, no dreamer is too small
Joined: 14 Jul 2010
Posts: 398
Re: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram  [#permalink]

Show Tags

New post 10 Dec 2011, 12:51
1
Liquid x in 8 kg = 8*30%=12/5
Liquid x in next 2 kg = 2*30% = 3/5
Total x = 12/5 + 3/5 = 15/5 = 3
so, (3/8)*100= 37.5%
Ans. C
_________________
Manager
Manager
avatar
Joined: 26 Apr 2011
Posts: 200
GMAT ToolKit User Reviews Badge
Re: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram  [#permalink]

Show Tags

New post 11 Dec 2011, 22:43
Initially we have 8kg of solution which has 3/10 0f 8= 2.4kg of X and 7/10 of 8 = 5.6kg of water after evaporation : 2.4kg of X and 3.6kg of water
Now we added 2kg of solution Y --> 7/10 of 2=1.4Kg water + 3/10 0f 2 =0.6Kg X
So we have left 5Kg Water & 3Kg X

Percentage concentration is (3/5)*100 or 37.5%
Manager
Manager
User avatar
Joined: 28 Jul 2011
Posts: 153
Re: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram  [#permalink]

Show Tags

New post 02 Jun 2012, 08:51
1
Solution Y total = 8
Liq x = 30% (8) = 2.4

Added 2 kg of Solution Y
Liq x = 30% (2) = 0.6

Final Solution wil have = (2.4 + 0.6) = 3 kg of Liq x

3/8 = 37.5%
Director
Director
User avatar
S
Joined: 17 Dec 2012
Posts: 620
Location: India
Re: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram  [#permalink]

Show Tags

New post 26 Aug 2013, 20:32
1
rovshan85 wrote:
Solution Y is 30 percent liquid X and 70 percent water. If 2 kilograms of water evaporate from 8 kilograms of solution Y and 2 kilograms of solution Y are added to the remaining 6 kilograms of liquid, what percent of this new solution is liquid X?

A. 30%
B. 33 1/3%
C. 37 1/2%
D. 40%
E. 50%

What is the easiest way to approach this type of problem and solve under 2 min.


1. The net effect of 2 kg of water evaporating and adding 2 kg of the solution is removing (-2 + 1.4 = -0.6) 0.6 kg of water and adding 0.6 kg of liquid
2 Therefore the changed solution contains, 2.4 + 0.6 = 3 kg of liquid and 5.6-0.6==5 kg of water.
3. Percentage of liquid is 3/8 * 100 % = 37 1/2 %
_________________
Srinivasan Vaidyaraman
Magical Logicians
https://magical-logicians-sat-gmat-gre.business.site

Holistic and Holy Approach
Senior Manager
Senior Manager
User avatar
Joined: 20 Aug 2015
Posts: 379
Location: India
GMAT 1: 760 Q50 V44
Re: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram  [#permalink]

Show Tags

New post 05 Jan 2016, 04:55
2
2
rtaha2412 wrote:
Solution Y is 30 percent liquid X and 70 percent water. If 2 kilograms of water evaporate from 8 kilograms of solutions Y and 2 kilograms of solution Y are added to the remaining 6 kilograms of liquid, what percent of this new liquid solution is liquid X?

A. 30%
B. 33 1/3%
C. 37 1/2%
D. 40%
E. 50%


The best way to solve these problems is to take one step at a time

Initial:
8 kg Solution Y
This means Solution X = 2.4 kg, Water = 5.6 kg

Step 2:
2 kg of water is evaporated.
Left over: Solution X = 2.4 kg and Water = 3.6 kg

Step 3:
2 kg of Solutoin Y is added
Or, 0.6 kg of Solution X and 1.4 kg of water is added

Final:
Solution X = 3, Water = 5
% of solution X = 3/8 * 100 = 37.5%

Option C
Intern
Intern
avatar
Joined: 01 Feb 2016
Posts: 1
Re: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram  [#permalink]

Show Tags

New post 03 May 2016, 06:47
rtaha2412 wrote:
Solution Y is 30 percent liquid X and 70 percent water. If 2 kilograms of water evaporate from 8 kilograms of solutions Y and 2 kilograms of solution Y are added to the remaining 6 kilograms of liquid, what percent of this new liquid solution is liquid X?

A. 30%
B. 33 1/3%
C. 37 1/2%
D. 40%
E. 50%



Hi,

I like using a table for mixture problems. This is what I came up with (see attachement):
Attachments

Sol gmat.JPG
Sol gmat.JPG [ 31.44 KiB | Viewed 11030 times ]

VP
VP
avatar
P
Joined: 07 Dec 2014
Posts: 1233
Re: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram  [#permalink]

Show Tags

New post Updated on: 28 Feb 2018, 21:08
Solution Y is 30 percent liquid X and 70 percent water. If 2 kilograms of water evaporate from 8 kilograms of solutions Y and 2 kilograms of solution Y are added to the remaining 6 kilograms of liquid, what percent of this new liquid solution is liquid X?

A. 30%
B. 33 1/3%
C. 37 1/2%
D. 40%
E. 50%

let x=% of liquid X in new solution
.3*8+.3*2=x(6+2)
x=3/8=37.5%
C

Originally posted by gracie on 18 Jul 2016, 19:23.
Last edited by gracie on 28 Feb 2018, 21:08, edited 1 time in total.
Manager
Manager
avatar
S
Joined: 14 Jul 2014
Posts: 86
Location: India
Concentration: Social Entrepreneurship, Strategy
GMAT 1: 620 Q41 V34
WE: Information Technology (Computer Software)
Re: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram  [#permalink]

Show Tags

New post 22 Sep 2018, 05:52
1
DS00 wrote:
rtaha2412 wrote:
Solution Y is 30 percent liquid X and 70 percent water. If 2 kilograms of water evaporate from 8 kilograms of solutions Y and 2 kilograms of solution Y are added to the remaining 6 kilograms of liquid, what percent of this new liquid solution is liquid X?

A. 30%
B. 33 1/3%
C. 37 1/2%
D. 40%
E. 50%



Hi,

I like using a table for mixture problems. This is what I came up with (see attachement):


I also used the similar approach.
To Sum up:
Initial 8 kilograms of Y consist of 2.4 kg X and 5.6 kg water.
We then lose 2 kg water to evaporation, so we are down to 3.6 kg water.
The final step adds 2 kg Y, which consists of .6 kg X and 1.4 kg water.
Therefore, the final mixture contains 3 kg X and 5 kg water. 3/8 = 37.5%.
Intern
Intern
avatar
Joined: 31 Mar 2017
Posts: 8
Re: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram  [#permalink]

Show Tags

New post 13 Dec 2018, 23:02
30% of 8 + 30% of 2 = 3 = X
X/T= 3/8 = 0.375 =37.5%

Posted from my mobile device
Manager
Manager
avatar
S
Joined: 05 Oct 2017
Posts: 102
Location: India
Concentration: Finance, International Business
Schools: ISB '21, IIMA , IIMB
GPA: 4
WE: Analyst (Energy and Utilities)
GMAT ToolKit User Premium Member CAT Tests
Re: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram  [#permalink]

Show Tags

New post 29 Dec 2018, 01:52
rtaha2412 wrote:
Solution Y is 30 percent liquid X and 70 percent water. If 2 kilograms of water evaporate from 8 kilograms of solutions Y and 2 kilograms of solution Y are added to the remaining 6 kilograms of liquid, what percent of this new liquid solution is liquid X?

A. 30%
B. 33 1/3%
C. 37 1/2%
D. 40%
E. 50%

Project PS Butler : Question #106


Subscribe to get Daily Email - Click Here | Subscribe via RSS - RSS


8 kg of the solution contains (8*0.3) kg = 2.4 kg of X

again,

2 kg of the add solution which is added will have 2*0.3 = 0.6 kg of X

Total final volume of the solution = 8 kg

Hence, % of X = (2.4+0.6)/8*100 = 3/8 * 100 =3* 12.5 = 37.5 %

Hence C)
Senior Manager
Senior Manager
User avatar
G
Joined: 12 Sep 2017
Posts: 313
Re: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram  [#permalink]

Show Tags

New post 02 Jan 2019, 19:22
Hello!

Tricky question, these topics is very challenging for me.

Is it possible to solve it with weighted averages?

Kind regards!
Manager
Manager
avatar
S
Joined: 22 Sep 2018
Posts: 236
Re: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram  [#permalink]

Show Tags

New post 22 Jan 2019, 16:14
rtaha2412 wrote:
Solution Y is 30 percent liquid X and 70 percent water. If 2 kilograms of water evaporate from 8 kilograms of solutions Y and 2 kilograms of solution Y are added to the remaining 6 kilograms of liquid, what percent of this new liquid solution is liquid X?

A. 30%
B. 33 1/3%
C. 37 1/2%
D. 40%
E. 50%


My reasoning:

8kg original solution is 30% X and 70% water or \(\frac{24}{10}kg liquid X and \frac{56}{10}kg water\)

Since we are looking for the percent of liquid X in our mixture we don't really care about the water in our solution.

We know that the total weight is 8kg and we are adding 2kg of solution Y, which has \(\frac{6}{10}kg liquid X\).

\(\frac{24}{10} + \frac{6}{10} = 3kg\) liquid X in the total solution.

\(\frac{3}{8} = 37.5%\)
VP
VP
User avatar
D
Joined: 09 Mar 2016
Posts: 1221
Re: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram  [#permalink]

Show Tags

New post 28 Jan 2019, 13:05
1
rtaha2412 wrote:
Solution Y is 30 percent liquid X and 70 percent water. If 2 kilograms of water evaporate from 8 kilograms of solutions Y and 2 kilograms of solution Y are added to the remaining 6 kilograms of liquid, what percent of this new liquid solution is liquid X?

A. 30%
B. 33 1/3%
C. 37 1/2%
D. 40%
E. 50%

Project PS Butler : Question #106


Subscribe to get Daily Email - Click Here | Subscribe via RSS - RSS



Solution Y is 30 percent liquid X and 70 percent water


Total 8 litres

8 *0.3 = 2.4 kg liquid

5.6 kg = water

2 kilograms of water evaporate from 8 kilograms of solutions Y

so 5.6 -2 = 3.6 water is left

afterwards 2 kilograms of solution Y are added to the remaining 6 kilograms of liquid

Since, solution Y cosists of 30 percent is liquid X and 70 percent is water

hence 2 *0.3 = 0.6 kg is liquid and 2-0.4 = 1.4 is water

2.4 +0.6 = 3 kg liquid

3.6+1.4 = 5 kg water

what percent of this new liquid solution is liquid X?

\(\frac{3}{8} = 0.37\) :grin:
Target Test Prep Representative
User avatar
V
Status: Founder & CEO
Affiliations: Target Test Prep
Joined: 14 Oct 2015
Posts: 9443
Location: United States (CA)
Re: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram  [#permalink]

Show Tags

New post 01 Jan 2020, 18:42
rtaha2412 wrote:
Solution Y is 30 percent liquid X and 70 percent water. If 2 kilograms of water evaporate from 8 kilograms of solutions Y and 2 kilograms of solution Y are added to the remaining 6 kilograms of liquid, what percent of this new liquid solution is liquid X?

A. 30%
B. 33 1/3%
C. 37 1/2%
D. 40%
E. 50%

Project PS Butler : Question #106


Subscribe to get Daily Email - Click Here | Subscribe via RSS - RSS



Originally, solution Y has 0.3 x 8 = 2.4 kg of liquid X and 0.7 x 8 = 5.6 kg of water. After 2 kg of water evaporate, solution Y has 2.4 kg of liquid X and 3.6 kg of water. However, since 2 kg of solution Y (of which, 0.3 x 2 = 0.6 kg is liquid X and 0.7 x 2 = 1.4 kg is water) are added back to the remaining 6 kilograms of solution Y, solution Y now has 2.4 + 0.6 = 3 kg of liquid X and 3.6 + 1.4 = 5 kg of water). Therefore, the percent of the new solution is liquid X is 3/(3 + 5) = 3/8 = 37.5%.

Answer: C
_________________

Scott Woodbury-Stewart

Founder and CEO

Scott@TargetTestPrep.com
TTP - Target Test Prep Logo
181 Reviews

5-star rated online GMAT quant
self study course

See why Target Test Prep is the top rated GMAT quant course on GMAT Club. Read Our Reviews

If you find one of my posts helpful, please take a moment to click on the "Kudos" button.

GMAT Club Bot
Re: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram   [#permalink] 01 Jan 2020, 18:42
Display posts from previous: Sort by

Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram

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





Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne