It is currently 24 Jun 2017, 19:12

### 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

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

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# Of a group of people surveyed, 75% have a computer, 62% have

Author Message
Director
Joined: 17 Oct 2005
Posts: 928
Of a group of people surveyed, 75% have a computer, 62% have [#permalink]

### Show Tags

23 Feb 2006, 06:23
This topic is locked. If you want to discuss this question please re-post it in the respective forum.

Of a group of people surveyed, 75% have a computer, 62% have a cd burner. What percent of the people have a computer but not a cd burner?

I. 11% of the people have a cd burner but not a computer
II. The number of people who have both is 3 times the number of people that have neither
VP
Joined: 29 Dec 2005
Posts: 1341

### Show Tags

23 Feb 2006, 08:29
joemama142000 wrote:
Of a group of people surveyed, 75% have a computer, 62% have a cd burner. What percent of the people have a computer but not a cd burner?

I. 11% of the people have a cd burner but not a computer
II. The number of people who have both is 3 times the number of people that have neither

joemama142000, you are the source of questions. that si gr8. your questions are real gmat type questions. what is the source?

i go with B.

75-3x+62-3x+x=100
x = 37/2=18.5%
Director
Joined: 10 Oct 2005
Posts: 718

### Show Tags

23 Feb 2006, 08:50
I am not sure but A for me.Used venn diagram it is 24 %
_________________

IE IMBA 2010

Intern
Joined: 20 Dec 2004
Posts: 21

### Show Tags

23 Feb 2006, 09:09
I think it is d

I suff -> if 11% have a cd burner but not a computer than 51% (62%-11%) have both -> thereof 24% have only a computer

II suff
Manager
Joined: 08 Feb 2006
Posts: 126

### Show Tags

23 Feb 2006, 10:30
I think D. Although I didn't get same percentage for people having a computer but no burner.
I. Venn Diagram 24%
2. 75-3x+3x+62-3x+x
Manager
Joined: 14 Jun 2005
Posts: 99

### Show Tags

23 Feb 2006, 10:55
I got D but with diff values

I.
Both + Burner/no Comp = 62
Both + no Burner/Comp = 75

From I, Burner/no Comp = 11,
Both + 11 = 62
Both = 51

51 + no Burner/Comp = 75
no Burner/Comp = 24
SUFF

II.

Both = 3(Neither)
Both + Burner/no Comp = 62
Both + no Burner/Comp = 75

62 + 75 - 3(Neither) + Neither = 100
Neither = 37/2
Both = 3(37/2)

no Burner/Comp = 75-3(37/2)
SUFF
Senior Manager
Joined: 13 Jun 2005
Posts: 252
Location: Haverhill, MA

### Show Tags

23 Feb 2006, 11:31
I go with D too..

But my only doubt is this.

I have never seen a DS problem with answer D and the 2 conditions not leading to the same answer.

here our answers are different. !!
Intern
Joined: 20 Dec 2004
Posts: 21

### Show Tags

23 Feb 2006, 15:04
i have my doubts for b -> it just mentions numbers and not % can we solve it anyway? i am not sure but i think Stat I and Stat II should come to the same result or?
Director
Joined: 17 Oct 2005
Posts: 928

### Show Tags

23 Feb 2006, 16:50
joemama142000 wrote:
Of a group of people surveyed, 75% have a computer, 62% have a cd burner. What percent of the people have a computer but not a cd burner?

I. 11% of the people have a cd burner but not a computer
II. The number of people who have both is 3 times the number of people that have neither

I think it is A because this is a trick question. tomg brought up a good point

the second is only talking about numbers and not percentages.

there for you can't use 3x and x. in that equation for the venn diagram
for all we know it can be 1 and 3 or 3 and 9 or whatever. The answer will result in different numbers.

plug in numbers to see for yourselves

G1+ G2+N-B=T
75+62+x-3x=100
---------1,3
---------3,9

btw all of my stuff is from either og11, 1000series, 800score, or other forum posts.
GMAT Club Legend
Joined: 07 Jul 2004
Posts: 5043
Location: Singapore

### Show Tags

23 Feb 2006, 20:18
Own computer only: 75-n
Own computer and cd burner: n
Own cd burner only but no computer (strange but this is just math): 62-n
Neither: n-37

1) Sufficient. We can work out the number of people who have both, and then subtract that from 75%.

2) Let x be number of people surveyed
n/100(x) = 3 * (n-37)/100 * x
x can be cancelled from both sides. The same for 1/100

n = 3(n-37)
Can solve for n.

Sufficient.

Ans D
CEO
Joined: 20 Nov 2005
Posts: 2894
Schools: Completed at SAID BUSINESS SCHOOL, OXFORD - Class of 2008

### Show Tags

23 Feb 2006, 22:29
It must be D.

Statement1 is easy and answer comes out to be 24%.

Statement2:
Let Total people surveyed = x
Then People who have computer = 0.75x
Peopel who have CD burner = 0.6x

Let people who have neither = a
Then peopel who have both = 3a

Then

0.75x-3a + 0.62x +a = x

Solve for a then we get a = 0.185x

So people who have both = 3 * 0.185x = 0.555x

Now people who have computer but not a cd burner = 0.75x - 0.555x = 0.195x i.e 19.5 %.

But this is among few DS problems that results in two different answer from two statements.
_________________

SAID BUSINESS SCHOOL, OXFORD - MBA CLASS OF 2008

Manager
Joined: 20 Feb 2006
Posts: 213

### Show Tags

23 Feb 2006, 23:02
Me for A since second statement does not speak in terms of %s.
VP
Joined: 29 Dec 2005
Posts: 1341

### Show Tags

24 Feb 2006, 22:45
Professor wrote:
joemama142000 wrote:
Of a group of people surveyed, 75% have a computer, 62% have a cd burner. What percent of the people have a computer but not a cd burner?

I. 11% of the people have a cd burner but not a computer
II. The number of people who have both is 3 times the number of people that have neither

i go with B.

75-3x+62-3x+x=100
x = 37/2=18.5%

sorry guys. i didnot read the question properly so i overlooked it. i should correct it.

from i,
computer =75
cd =62
only cd= 11
c+cd= 62-11=51
only computer = 75-51=24
so the percent of the people who have a computer but not a cd burner = 24

from ii,
nither = x
both = 3x

c+cd- both + nither = 100
75 + 62 -3x + x = 100
2x = 137-100
x = 37/2

this also gives the answer but the answers are contradictory to each other. therefore, this question is also poorly worded.
VP
Joined: 29 Apr 2003
Posts: 1403

### Show Tags

28 Feb 2006, 04:02
I think its D.

1. Can use Venn Diagrams
2. Can use extentionsion of venn diagrams with the additional data given.

Whats the OA?
Manager
Joined: 24 Dec 2005
Posts: 95

### Show Tags

28 Feb 2006, 09:18
Good question. Must Know OA I go with A.
VP
Joined: 20 Sep 2005
Posts: 1017

### Show Tags

28 Feb 2006, 11:02
D is right.

I have never seen an official problem in which the two statements contradict each other.
28 Feb 2006, 11:02
Display posts from previous: Sort by