GMAT Club Around The World!!! What percent of the members of a club at

Question

What percent of the members of a club attended a certain conference?

(1) Twice as many members attended the conference as didn't attend the conference.
(2) There are 90 members in the club.

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Kinshook · Answer

Asked: What percent of the members of a club attended a certain conference?

(1) Twice as many members attended the conference as didn't attend the conference.
The percent of the members of a club attended a certain conference = (2/3)*100 = 66.66%
SUFFICIENT

(2) There are 90 members in the club.
There is no information about the number of members who attended the conference.
NOT SUFFICIENT

IMO A

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zhanbo · Answer

The answer is  (A) . Question is: What percent of the members of a club attended a certain conference?

Sometimes it pays to check (2) first esp. if it is very straightforward.

(2) There are 90 members in the club.
Clearly it cannot answer the question. 
INSUFFICIENT.

(1) Twice as many members attended the conference as didn't attend the conference.
So 2/3 members attended the conference. 
SUFFICIENT.

ananya3 · Answer

IMO A

people attended = A
didn't attend = D
total = T
people who attended the conference = X% of total
percent attended = A/T * 100

(1) Twice as many members attended the conference as didn't attend the conference.
2D = A
3D = T
D/T = 1/3
(T-A)/T = 1/3
1- A/T = 1/3
A/T = 2/3
 Sufficient

(2) There are 90 members in the club.
T= 90
A =?? 
 Not sufficient

Deepakjhamb · Answer

What percent of the members of a club attended a certain conference?

(1) Twice as many members attended the conference as didn't attend the conference.
(2) There are 90 members in the club.

statement 1 : lets have members not attending = x , then members attending = 2x so % of members attending = 2x/3x *100 = 66.66%

so statement 1 is sufficient

statement 2 : total club members = 90 , so not sufficient

so answer is a)

BIDJI23 · Answer

From A&B, we know the %
Too easy? Let's check the prop' one by one as  math  Revolution learned me!

From A, we understand that 2/3 have participated because it's the double of 1/3. So we have a single answer to the question

From B, we get no answer to the question.

PUSH A

rocky620 · Answer

(1) Twice as many members attended the conference as didn't attend the conference.
let x be the number of people who did not attended the conference. So, 2x attended the conference.

%of people who attended = (2x/3x)*100 = 66.7%

Sufficient.

(2) There are 90 members in the club.

Insufficient

IMO Option A

TarunKumar1234 · Answer

What percent of the members of a club attended a certain conference?

(1) Twice as many members attended the conference as didn't attend the conference.
(2) There are 90 members in the club.

statement 1 : lets have members not attending = x , then members attending = 2x so % of members attending = 2x/3x *100 = 66.66%

so statement 1 is sufficient

statement 2 : total club members = 90 , so not sufficient

so answer is a)

Green2k1 · Answer

Correct Answer A

What percent of the members of a club attended a certain conference?

(1) Twice as many members attended the conference as didn't attend the conference.
Att ended the conference =2x
not attended the conference =x

Percent of member attended = 2x*100/3x
-sifficient 
 
(2) There are 90 members in the club.
 - no other data available
- not sufficient

manasi05 · Answer

We have to find the percent of the members of a club who attended the conference 
To find this we will need the total number or members and number of members who attended or not attended the conference.

Statement 1
Let no. of members who attended the conference = a
No of members who didn’t attend the conference = b
From the statement 
2(a) = b

We just know the ratio and no details about the total number of member. Hence not sufficient to find the percentage

Statement 2
Total no. of member in the club = 90
a+b = 90
We know nothing about the no. of member who of members who attended or not attended the conference.
So Insufficient.

Combining statement 1 and 2 we have
2a = b
a + b = 90
From this we can find the value of no. of members who attended the conference
a=30
Now that we have the total number of members and number of members who attended the conference we can find the value of the percent of the members who attended the conference 
Hence Sufficient

So the answer will be C

GMAT Club Around The World!!! What percent of the members of a club at

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