Author 
Message 
TAGS:

Hide Tags

Manager
Joined: 05 Jul 2006
Posts: 195

In a certain region, the number of children who have been [#permalink]
Show Tags
06 Sep 2006, 12:15
8
This post received KUDOS
37
This post was BOOKMARKED
Question Stats:
67% (01:09) correct 33% (01:15) wrong based on 965 sessions
HideShow timer Statistics
In a certain region, the number of children who have been vaccinated against rubella is twice the number who have been vaccinated against mumps. The number who have been vaccinated against both is twice the number who have been vaccinated only against mumps. If 5,000 have been vaccinated against both, how many have been vaccinated only against rubella? A. 2,500 B. 7,500 C. 10,000 D. 15,000 E. 17,500
Official Answer and Stats are available only to registered users. Register/ Login.



VP
Joined: 02 Jun 2006
Posts: 1248

Re: In a certain region, the number of children who have been [#permalink]
Show Tags
06 Sep 2006, 13:57
2
This post received KUDOS
3
This post was BOOKMARKED
C. 10,000
Let
R = vaccinated against Rubella
M = vaccinated against Measles
R'= not vaccinated against Rubella
M'= not vacinnated against Measles
Given RM = 5000, and R'M = 1/2 RM = 2500
M = 7500
R = 2 x M = 15000
RM' = R  RM = 15000  5000 = 10, 000
Answer: C



Retired Moderator
Joined: 05 Jul 2006
Posts: 1741

Re: In a certain region, the number of children who have been [#permalink]
Show Tags
06 Sep 2006, 15:27
2
This post received KUDOS
Folks i tried to solve it using venn diagrams still cant get it
I will appreciate any explanation that is not based on a formula that i have to revise( am ver bad at revising formulas)



VP
Joined: 02 Jun 2006
Posts: 1248

Re: In a certain region, the number of children who have been [#permalink]
Show Tags
06 Sep 2006, 15:42
7
This post received KUDOS
2
This post was BOOKMARKED
Mt = Number vaccinated against Mumps
x = Number vaccinated against Mumps but not Rubella
Looking at the attached figure, if the number of Rubella and not mumps vaccinated is 5000 *( which is 2x) then x = 2500 which is the number vaccinated against Mumps but not Rubella.
Total vaccinated against Mumps = 7500
Total vaccinated against Rubella = 2 x Mt = 15000
Therefore, total Rubella but not Mumps vaccinated = 15000  5000 = 10, 000
yezz wrote: Folks i tried to solve it using venn diagrams still cant get it I will appreciate any explanation that is not based on a formula that i have to revise( am ver bad at revising formulas)
Attachments
Rubella.JPG [ 12.38 KiB  Viewed 29914 times ]



CEO
Joined: 20 Nov 2005
Posts: 2863
Schools: Completed at SAID BUSINESS SCHOOL, OXFORD  Class of 2008

Re: In a certain region, the number of children who have been [#permalink]
Show Tags
07 Sep 2006, 07:31
4
This post received KUDOS
3
This post was BOOKMARKED
C
Make Venn Diagram.
Mumps = x
Rubella = 2x
Both = y
Only Mumps = xy
As given y = 2(xy)
i.e 3y = 2x
y = 5000
therefore x = 7500
Only Rubella = 2xy = 2*7500  5000 = 10000
_________________
SAID BUSINESS SCHOOL, OXFORD  MBA CLASS OF 2008



Senior Manager
Joined: 27 Jul 2006
Posts: 290

Re: In a certain region, the number of children who have been [#permalink]
Show Tags
08 Sep 2006, 09:34
2
This post received KUDOS
We know that 5000 people have both MR vac.
We know that 2500 people have only M
Total people with M vac is 7500
we know that total R=2M
15000
we also know that 5000 people have both MR
15000
5000
=10000



Senior Manager
Joined: 17 Jun 2015
Posts: 254
GMAT 1: 540 Q39 V26 GMAT 2: 680 Q46 V37

Re: In a certain region, the number of children who have been [#permalink]
Show Tags
13 Sep 2016, 18:20
A = Only Rubella B = Both C = Only Mumps A + B = Total Rubella B + C = Total Mumps According to the question, A + B = 2 ( B+ C )  (Eqn 1) B = 2C B = 5000 A + B = 2B + 2C ; A = B + 2C = 2B = 10,000 Option C.
_________________
Fais de ta vie un rêve et d'un rêve une réalité



Veritas Prep GMAT Instructor
Joined: 16 Oct 2010
Posts: 8001
Location: Pune, India

Re: In a certain region, the number of children who have been [#permalink]
Show Tags
13 Sep 2016, 23:05
7
This post received KUDOS
Expert's post
1
This post was BOOKMARKED
lan583 wrote: In a certain region, the number of children who have been vaccinated against rubella is twice the number who have been vaccinated against mumps. The number who have been vaccinated against both is twice the number who have been vaccinated only against mumps. If 5,000 have been vaccinated against both, how many have been vaccinated only against rubella?
A. 2,5000 B. 7,500 C. 10,000 D. 15,000 E. 17,500 Use a single variable as far as possible. Number vaccinated only against mumps = x Number vaccinated against both = 2x = 5000 (so x = 2500) Then, number vaccinated against mumps (including both) = x + 2x = 3x Number vaccinated against rubella = 2*3x = 6x Then, number vaccinated against only rubella = 6x  2x = 4x = 4*2500 = 10,000 Answer (C)
_________________
Karishma Veritas Prep  GMAT Instructor My Blog
Get started with Veritas Prep GMAT On Demand for $199
Veritas Prep Reviews



Manager
Joined: 13 Dec 2013
Posts: 168
Location: United States (NY)
Concentration: Nonprofit, International Business
GMAT 1: 710 Q46 V41 GMAT 2: 720 Q48 V40
GPA: 4
WE: Consulting (Consulting)

Re: In a certain region, the number of children who have been [#permalink]
Show Tags
21 Mar 2017, 19:30
lan583 wrote: In a certain region, the number of children who have been vaccinated against rubella is twice the number who have been vaccinated against mumps. The number who have been vaccinated against both is twice the number who have been vaccinated only against mumps. If 5,000 have been vaccinated against both, how many have been vaccinated only against rubella?
A. 2,5000 B. 7,500 C. 10,000 D. 15,000 E. 17,500 Number vaccinated against both: 5,000. The number vaccinated against both is twice the number vaccinated only against mumps. Number vaccinated only against mumps = 5000/2=2500. Number vaccinated against mumps = 7500 Number vaccinated against rubella = 5000 + n 5000+n=2*7500 5000+n=15000 n=10000 Kudos if you agree with the explanation! Please comment if you have a better method.



Manager
Joined: 20 Jan 2016
Posts: 217

Re: In a certain region, the number of children who have been [#permalink]
Show Tags
06 Nov 2017, 04:06
I used the table format similar to the one provided by haas_mba07 above.
Try to fill in the table systematically.
We are told that RM=5000 R=2M
When you draw the table, fill in the value for RM first (5000).
Now RM= 2M' (only mumps, not rubella)
So on the right hand side, you will write 2500.
This gives you a total for M which is 7500
Now, We are given that R=2M
So in the similar column under 5000, you will write value of R which will be 150,000
Now to get the value of R' (only rubella , not mumps) by subtracting 150,0005000 = 10,000 (option C)



Target Test Prep Representative
Status: Head GMAT Instructor
Affiliations: Target Test Prep
Joined: 04 Mar 2011
Posts: 2155

Re: In a certain region, the number of children who have been [#permalink]
Show Tags
08 Nov 2017, 17:24
lan583 wrote: In a certain region, the number of children who have been vaccinated against rubella is twice the number who have been vaccinated against mumps. The number who have been vaccinated against both is twice the number who have been vaccinated only against mumps. If 5,000 have been vaccinated against both, how many have been vaccinated only against rubella?
A. 2,500 B. 7,500 C. 10,000 D. 15,000 E. 17,500 We can create the following formula: Total = total mumps + total rubella  both + neither We can let total mumps = m, and thus total rubella = 2m. We can let both = b, and thus only mumps is m  b. Since the number who have been vaccinated against both is twice the number who have been vaccinated only against mumps: b = 2(m  b) b = 2m  2b 3b = 2m Since b = 5000, we have: 3(5000) = 2m 15000 = 2m 7500 = m Since m = 7500, the total number of children vaccinated against rubella is r = 2m = 2(7500) = 15000. Thus, the number who have been vaccinated against only rubella is r  b = 15000  5000 = 10000. Answer: C
_________________
Jeffery Miller
Head of GMAT Instruction
GMAT Quant SelfStudy Course
500+ lessons 3000+ practice problems 800+ HD solutions



Senior Manager
Status: love the club...
Joined: 24 Mar 2015
Posts: 283

Re: In a certain region, the number of children who have been [#permalink]
Show Tags
25 Nov 2017, 03:23
1
This post received KUDOS
In a certain region, the number of children who have been vaccinated against rubella is twice the number who have been vaccinated against mumps. The number who have been vaccinated against both is twice the number who have been vaccinated only against mumps. If 5,000 have been vaccinated against both, how many have been vaccinated only against rubella?
A. 2,500 B. 7,500 C. 10,000 D. 15,000 E. 17,500[/quote]
hi
both = 5000 only mumps = 2500 so, mumps = 7500
now, r = 2 * 7500 = 15000
only rubella = 15000  5000 =10000
thanks



Senior Manager
Joined: 15 Jan 2017
Posts: 360

Re: In a certain region, the number of children who have been [#permalink]
Show Tags
11 Dec 2017, 13:20
1
This post received KUDOS
Did it mostly like a word problem: In a certain region, the number of children who have been vaccinated against rubella is twice the number who have been vaccinated against mumps. The number who have been vaccinated against both is twice the number who have been vaccinated only against mumps. If 5,000 have been vaccinated against both, how many have been vaccinated only against rubella? " In a certain region, the number of children who have been vaccinated against rubella is twice the number who have been vaccinated against mumps." > mumps = x, rubella = 2x " The number who have been vaccinated against both is twice the number who have been vaccinated only against mumps. "  both would mean 2x +x = 3x have been vaxxed against both. So twice of this => 3x = 2x of mumps => 3x  2x =0, x = 1 both, as per question. Thus mumps and 'both' are the same. "If 5,000 have been vaccinated against both, how many have been vaccinated only against rubella?" > says that x = 5000. So rubella, as per earlier, is 10,000. Kudos, please if it was useful for you




Re: In a certain region, the number of children who have been
[#permalink]
11 Dec 2017, 13:20






