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Mariela
 
 

OG - DS - #121

by Mariela Wed Jun 13, 2007 9:26 pm

If x/2=3/y is x less than y?
1)y>=3
2)y<=4

OK, I don't see I''m settin up xy=6 and then x=6/y so the question is really is x=6/y?

If so
Statement one says that xis 6/ (>3) or x>=2, so how exactly is this sufficient?


Idon't get the explanation of statement 2 at all.

Would appreciate your help.

Thanks,
Mariela
GMAT 5/18
 
 

by GMAT 5/18 Thu Jun 14, 2007 1:10 am

Mariela,

Here is how I would solve this problem:

Step 1: Rephrase the question to xy = 6

Step 2: See if Statement I is sufficient.

If y is greater than or equal to 3, then x has to be less than or equal to 2. A few examples to prove this:

xy = 6, so if y = 3, then x = 2; if y = 4, x = 1.5; etc.

We can state that x is always less than y. Therefore, statement I is sufficient.

Step 3: See if Statement II is sufficient.

If y is less than or equal to 4, then x has to be greater than or equal to 1.5. A few examples to prove this:

xy = 6, so if y =4, then x = 1.5; if y = 2, x = 3; etc.

Statement II alone allows y to be either greater than, less than, or equal to x. Therefore, insufficient.

A is the answer.

Hope that helps!
dbernst
ManhattanGMAT Staff
 
Posts: 300
Joined: Mon May 09, 2005 9:03 am
 

OG 11th ed Data sufficiency # 121

by dbernst Thu Jun 14, 2007 11:52 am

GMAT 5/18, thanks for the explanation.

Mariela, it is extremely important on Data Sufficiency to practice carefully rephrasing the original question. In this case, however, the xy=6 was not part of the question. Instead, it was additional factual information for you to use as you solve each statement. Normally, this factual information will be separated from the question by the word "if." In the problem at hand, the question remains as stated: Is x less than y?

-dan