Apr 21 10:00 PM PDT  11:00 PM PDT $84 + an extra $10 off for the first month of EMPOWERgmat access. Train to be ready for Round 3 Deadlines with EMPOWERgmat's Score Booster. Ends April 21st Code: GCENHANCED Apr 21 07:00 AM PDT  09:00 AM PDT Get personalized insights on how to achieve your Target Quant Score. Apr 22 08:00 AM PDT  09:00 AM PDT What people who reach the high 700's do differently? We're going to share insights, tips, and strategies from data we collected on over 50,000 students who used examPAL. Save your spot today! Apr 23 08:00 PM EDT  09:00 PM EDT Strategies and techniques for approaching featured GMAT topics. Tuesday, April 23rd at 8 pm ET Apr 24 08:00 PM EDT  09:00 PM EDT Maximize Your Potential: 5 Steps to Getting Your Dream MBA Part 3 of 5: Key TestTaking Strategies for GMAT. Wednesday, April 24th at 8 pm ET Apr 25 10:00 PM PDT  11:00 PM PDT Join an exclusive workshop for GMAT Club members and learn how to cut your preparation time by 50% and still reach a 700+ on the GMAT. Limited for the first 99 registrants. Register today! Apr 27 07:00 AM PDT  09:00 AM PDT Attend this webinar and master GMAT SC in 10 days by learning how meaning and logic can help you tackle 700+ level SC questions with ease. Apr 28 07:00 AM PDT  09:00 AM PDT Attend this webinar to learn a structured approach to solve 700+ Number Properties question in less than 2 minutes.
Author 
Message 
TAGS:

Hide Tags

SVP
Status: It's near  I can see.
Joined: 13 Apr 2013
Posts: 1596
Location: India
Concentration: International Business, Operations
GPA: 3.01
WE: Engineering (Real Estate)

There are two examinations rooms A and B. If 10 students are sent from
[#permalink]
Show Tags
08 Apr 2019, 23:03
Question Stats:
65% (02:19) correct 35% (02:25) wrong based on 52 sessions
HideShow timer Statistics
There are two examinations rooms A and B. If 10 students are sent from A to B, then the number of students in each room is the same. If 20 candidates are sent from B to A, then the number of students in A is double the number of students in B. The number of students in room A is a. 20 b. 80 c. 100 d. 150 e. 200
Official Answer and Stats are available only to registered users. Register/ Login.
_________________
"Do not watch clock; Do what it does. KEEP GOING."



Math Expert
Joined: 02 Aug 2009
Posts: 7573

Re: There are two examinations rooms A and B. If 10 students are sent from
[#permalink]
Show Tags
09 Apr 2019, 19:36
AkshdeepS wrote: There are two examinations rooms A and B. If 10 students are sent from A to B, then the number of students in each room is the same. If 20 candidates are sent from B to A, then the number of students in A is double the number of students in B. The number of students in room A is
a. 20
b. 80
c. 100
d. 150
e. 200 If 10 students are sent from A to B, then the number of students in each room is the same MEANS A=B+20, (as A10=B+10)If 20 candidates are sent from B to A, then the number of students in A is double the number of students in B. MEANS 2(B20)=A+20. Substitute A as B+20.. => 2B40=B+20+20...B=80, so A=B+20=80+20=100.. OR We can work from choices.. a. 20.... so B=0...Not possible b. 80...... so B=60.. When 20 are given from B : B=40 and A=100...NO c. 100...... so B=80.. When 20 are given from B : B=60 and A=120... YES 120 =2*60 C
_________________



CEO
Joined: 18 Aug 2017
Posts: 3006
Location: India
Concentration: Sustainability, Marketing
GPA: 4
WE: Marketing (Energy and Utilities)

Re: There are two examinations rooms A and B. If 10 students are sent from
[#permalink]
Show Tags
11 Apr 2019, 09:57
AkshdeepS wrote: There are two examinations rooms A and B. If 10 students are sent from A to B, then the number of students in each room is the same. If 20 candidates are sent from B to A, then the number of students in A is double the number of students in B. The number of students in room A is
a. 20
b. 80
c. 100
d. 150
e. 200 AkshdeepS why is this question being tagged as 700? solution is <30 secs let students A = x and class B = y we need to find value of x case 1 ; x10=y10 so y = x20 ( a) case 2; x+20= 2*(y20) x+20 = 2y40 substitute value of y from (a) we get x+20= 2*(x20)40 x+20=2x4040 or say x= 100 IMO C
_________________
If you liked my solution then please give Kudos. Kudos encourage active discussions.



SVP
Status: It's near  I can see.
Joined: 13 Apr 2013
Posts: 1596
Location: India
Concentration: International Business, Operations
GPA: 3.01
WE: Engineering (Real Estate)

There are two examinations rooms A and B. If 10 students are sent from
[#permalink]
Show Tags
11 Apr 2019, 10:12
Archit3110 wrote: AkshdeepS wrote: There are two examinations rooms A and B. If 10 students are sent from A to B, then the number of students in each room is the same. If 20 candidates are sent from B to A, then the number of students in A is double the number of students in B. The number of students in room A is
a. 20
b. 80
c. 100
d. 150
e. 200 AkshdeepS why is this question being tagged as 700? solution is <30 secs let students A = x and class B = y we need to find value of x case 1 ; x10=y10 so y = x20 ( a) case 2; x+20= 2*(y20) x+20 = 2y40 substitute value of y from (a) we get x+20= 2*(x20)40 x+20=2x4040 or say x= 100 IMO C Archit3110 : Stats of the question are also saying a 700+ level . Please think of people like me who are struggling in quant.
_________________
"Do not watch clock; Do what it does. KEEP GOING."



CEO
Joined: 18 Aug 2017
Posts: 3006
Location: India
Concentration: Sustainability, Marketing
GPA: 4
WE: Marketing (Energy and Utilities)

Re: There are two examinations rooms A and B. If 10 students are sent from
[#permalink]
Show Tags
11 Apr 2019, 10:22
AkshdeepS ; kind apologize but i did not mean to comment upon anyones skill or current preparation level, even I myself is sailing on the same boat called "GMAT" , well all I felt was that the question was of medium difficulty nevertheless until a question is relevant to gmat , it is then a good question to practise .. keep posting such good questions.. AkshdeepS wrote: Archit3110 wrote: AkshdeepS wrote: There are two examinations rooms A and B. If 10 students are sent from A to B, then the number of students in each room is the same. If 20 candidates are sent from B to A, then the number of students in A is double the number of students in B. The number of students in room A is
a. 20
b. 80
c. 100
d. 150
e. 200 AkshdeepS why is this question being tagged as 700? solution is <30 secs let students A = x and class B = y we need to find value of x case 1 ; x10=y10 so y = x20 ( a) case 2; x+20= 2*(y20) x+20 = 2y40 substitute value of y from (a) we get x+20= 2*(x20)40 x+20=2x4040 or say x= 100 IMO C Stats of the question is also saying a 700+ level . Please think of people like me who are struggling in quant.
_________________
If you liked my solution then please give Kudos. Kudos encourage active discussions.



SVP
Status: It's near  I can see.
Joined: 13 Apr 2013
Posts: 1596
Location: India
Concentration: International Business, Operations
GPA: 3.01
WE: Engineering (Real Estate)

There are two examinations rooms A and B. If 10 students are sent from
[#permalink]
Show Tags
11 Apr 2019, 10:32
Quote: AkshdeepS ; kind apologize but i did not mean to comment upon anyones skill or current preparation level, even I myself is sailing on the same boat called "GMAT" , well all I felt was that the question was of medium difficulty nevertheless until a question is relevant to gmat , it is then a good question to practise .. keep posting such good questions.. Archit3110 ; Not need to apologise bro as you said nothing sort of hurting. Neither you compared skills nor did you undermine anyone's. Good to have some lively chats and light moments, otherwise the GMAT journey is a pain that we expect to change in happiness sometime in future. We all are in the same boat till someone's profile shows a 700+ suddenly, and we think Ohh...one more left us behind.. Cheers: All the best.
_________________
"Do not watch clock; Do what it does. KEEP GOING."



CEO
Joined: 18 Aug 2017
Posts: 3006
Location: India
Concentration: Sustainability, Marketing
GPA: 4
WE: Marketing (Energy and Utilities)

Re: There are two examinations rooms A and B. If 10 students are sent from
[#permalink]
Show Tags
11 Apr 2019, 11:34
AkshdeepS wrote: Quote: AkshdeepS ; kind apologize but i did not mean to comment upon anyones skill or current preparation level, even I myself is sailing on the same boat called "GMAT" , well all I felt was that the question was of medium difficulty nevertheless until a question is relevant to gmat , it is then a good question to practise .. keep posting such good questions.. Archit3110 ; Not need to apologise bro as you said nothing sort of hurting. Neither you compared skills nor did you undermine anyone's. Good to have some lively chats and light moments, otherwise the GMAT journey is a pain that we expect to change in happiness sometime in future. We all are in the same boat till someone's profile shows a 700+ suddenly, and we think Ohh...one more left us behind.. Cheers: All the best. AkshdeepS .. thanks
_________________
If you liked my solution then please give Kudos. Kudos encourage active discussions.



Manager
Joined: 24 Nov 2018
Posts: 108
Location: India
GPA: 3.27
WE: General Management (Retail Banking)

Re: There are two examinations rooms A and B. If 10 students are sent from
[#permalink]
Show Tags
11 Apr 2019, 16:10
AkshdeepS wrote: There are two examinations rooms A and B. If 10 students are sent from A to B, then the number of students in each room is the same. If 20 candidates are sent from B to A, then the number of students in A is double the number of students in B. The number of students in room A is
a. 20
b. 80
c. 100
d. 150
e. 200 Let the number of students in room a and b = x and y. Eqn. 1:\(x10=y+10\) or \(xy=20\) Eqn2:\(x+20=2(y20)\) or \(2yx=60\) Solve for x and y \(x=100, y=80,\) IMO, Option C.
_________________
Kudos encourage discussions. Share it to amplify collective education!



Intern
Joined: 17 Jun 2017
Posts: 40

Re: There are two examinations rooms A and B. If 10 students are sent from
[#permalink]
Show Tags
11 Apr 2019, 23:46
Archit3110 wrote: AkshdeepS wrote: There are two examinations rooms A and B. If 10 students are sent from A to B, then the number of students in each room is the same. If 20 candidates are sent from B to A, then the number of students in A is double the number of students in B. The number of students in room A is
a. 20
b. 80
c. 100
d. 150
e. 200 AkshdeepS why is this question being tagged as 700? solution is <30 secs let students A = x and class B = y we need to find value of x case 1 ; x10=y10 so y = x20 ( a) case 2; x+20= 2*(y20) x+20 = 2y40 substitute value of y from (a) we get x+20= 2*(x20)40 x+20=2x4040 or say x= 100 IMO C Not everyone can be in the same shoes buddy ! Would request pundits not to judge.



Intern
Joined: 15 Jan 2018
Posts: 21

There are two examinations rooms A and B. If 10 students are sent from
[#permalink]
Show Tags
15 Apr 2019, 16:42
Another way to solve is to use the first condition as a qualifier for the second condition.
The first condition says, if 10 students are moved from A to B, then the class sizes are equal. This means that the difference in class sizes must be 20.
Now we must use the difference of 20 to qualify the answer choices for the second condition. We will phrase this as can 2*(20 less than the number in B) = A+20?
In the following math, just remember that B is 20 less than A, which is how I get 0, 60, and 80.
A. Does 2(020) = (20+20)? No.
B. Does 2(6020) = (80+20)? No.
C. Does 2(8020) = (100+20)? Yes! Answer C




There are two examinations rooms A and B. If 10 students are sent from
[#permalink]
15 Apr 2019, 16:42






