If 20 percent of the members in club A are members of club B also,

Question

If 20 percent of the members in club A are members of club B also, which club has more members?

(1) 30 percent of the members of B are members of A also. 
(2) A has 600 members.

gamjatang · Answer

If 20 percent of the members in club A are members of club B also, which club has more members?
 
1). 30 percent of the members of B are members of A also. 
2). A has 600 members.

X = number of members in club A
Y = number of members in club B

1) 

0.2X = 0.3Y
X = 3/2Y
X > Y
Sufficient

2) 
X = 600
Insufficient

Thus, (A).

saadis87 · Answer

and um...what if club A has 1000 members and B has 100?

Bunuel · Answer

A = 1000 and B = 100 would contradict info given in the stem. We are told that 20% of the members in club A are members of club B also, if there are 100 people in A, then it means that 200 of them are members of B too. Thus B cannot have less than 200 members.

From the stem we have that {Both} = 0.2A. (1) says that {Both}= 0.3B, hence 0.2A = 0.3B --> A/B = 3/2 --> A > B.

Hope it's clear.

anand.prakash90 · Answer

0.2X = 0.3Y is wrong, because it is not same , as it is not given those 20 % and 30 percent are common to both...

Bunuel · Answer

No, that's not correct. 20 percent of the members in club A are members of club B also, means that {Both} = 0.2A. 30 percent of the members of B are members of A also, means that {Both}= 0.3B. Therefore, 0.2A = 0.3B --> A/B = 3/2 --> A > B. Check OG question about the same concept: is-the-number-of-members-of-club-x-greater-than-the-number-128641.html

devikeerthan · Answer

1)0.2a = 0.3b
a = 3/2b
a > b
Sufficient

2)
a = 600
b = ?
insufficient
A it is

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If 20 percent of the members in club A are members of club B also,

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