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DS-When 1000 children were inoculated with

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sanath.kumar.patro
 Post subject: DS-When 1000 children were inoculated with
 Post Posted: Wed Jul 06, 2011 1:49 am 
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Students


Posts: 4
When 1000 children were inoculated with a certain vaccine some developed fever and some developed inflammation. How many children developed inflammation but not fever??

1. 880 children developed neither inflammation fever .
2. 20 children developed fever.

THIS IS A QUESTION FROM GMAT PREP.

My approach:-
1. no. of chlren who either got an inflammation or fever or both=1000-880=120
so insufficient

2. 20 chilren got fever
insufficient

combining 1 & 2 we get- 100 children are left that includes- no. of children effected by fever ONLY + no. of children effected by bot FEVER & inflaamation.

So we cant determine the number of children who are effected ony by the inflammation. Hence E
but the OA is C.
Am i missing something??
Can the instructors help, please????
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oren.yomorta
 Post subject: Re: DS-When 1000 children were inoculated with
 Post Posted: Mon Jul 11, 2011 2:14 pm 
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Students


Posts: 1
By saying some developed disease a and others developed disease b, the writers are telling us non developed both...

Hope that helps some...
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pranabiitkgp
 Post subject: Re: DS-When 1000 children were inoculated with
 Post Posted: Thu Jul 14, 2011 6:29 am 
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Forum Guests


Posts: 63
F-Oonly fever but not inflamation
x-having both
I - only inflamation.
F+x+I = 120
F+x = 20
So I = 100
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RonPurewal
 Post subject: Re: DS-When 1000 children were inoculated with
 Post Posted: Fri Jul 15, 2011 2:14 am 
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ManhattanGMAT Staff


Posts: 7146
sanath.kumar.patro wrote:
When 1000 children were inoculated with a certain vaccine some developed fever and some developed inflammation. How many children developed inflammation but not fever??

1. 880 children developed neither inflammation fever .
2. 20 children developed fever.

THIS IS A QUESTION FROM GMAT PREP.

My approach:-
1. no. of chlren who either got an inflammation or fever or both=1000-880=120
so insufficient

2. 20 chilren got fever
insufficient

combining 1 & 2 we get- 100 children are left that includes- no. of children effected by fever ONLY + no. of children effected by bot FEVER & inflaamation.

So we cant determine the number of children who are effected ony by the inflammation. Hence E
but the OA is C.
Am i missing something??
Can the instructors help, please????


use the double set matrix:
---------------------FEVER-----NO FEVER-----TOTAL
INFLAMMATION
NO INFLAMM.
TOTAL

statement (1):
---------------------FEVER-----NO FEVER-----TOTAL
INFLAMMATION
NO INFLAMM.--------------------880-----------
TOTAL-------------------------------------------1000
insufficient

statement (2):
---------------------FEVER-----NO FEVER-----TOTAL
INFLAMMATION
NO INFLAMM.
TOTAL----------------20-----------980----------1000
insufficient (although we can fill in 1000 - 20 = 980)

together:
---------------------FEVER-----NO FEVER-----TOTAL
INFLAMMATION-----------------100
NO INFLAMM.--------------------880-----------
TOTAL----------------20----------980----------1000
sufficient; 100 is the desired answer.
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