Need a info regarding DS statement patterns...

[samrat_bagchi]

Hi,
I have just started preparing for GMAT and have a question on my mind, troubling me... This is about the a clarity I need regarding DS statement patterns...
My question/concern is: is it possible that the 2 statements in a DS question shall help me come up with 2 separate answers? Don't know If was able to explain my question:
Let me give an example:
suppose: x=500/(1+Ctr) where C is a constant and t and r are variables. Find x when t=5, r=10?
Statement 1. values of t and r are given for a value of x
Statement 1. values of t' and r' are given for a value of x'

Now, as we understand X can be calculated, using any one of the statements below to find the value of the constant C.

Now, my question is: can such a situation ever appear in my GMAT DS question where, the 2 statements shall generate to separate values of C. The reason for asking this is:
1. If the situation shall never happen, I shall understand that both of the statements shall always give me the same C value and thus may not need to spend time to cross check the same with both the statements separately and save time.

Please pardon if my question was very dumb... :roll:

[Adam@Knewton]

A good question with a simple answer: NO. One of the rules of Data Sufficiency is that the Statements can never contradiction each other (or contradict any information already given as true in the prompt). If you get different values for Statements (1) and (2), or if you get a "Yes" from Statement (1) and a "No" from Statement (2), it in fact means you've done something wrong, as this is not allowed on the GMAT.

Sometimes this can actually be usefull strategically. Imagine a question where, after doing the math, you have the following thought process:

Question: Some Yes/No DS question.

Statement (1): I'm definitely positively sure that it's Sufficient and the answer is "No."
Statement (2): I'm pretty unclear about this, I tried numbers and got mostly "Yes" answers, so I think it's Sufficient, but ... huh?

In this case, your best bet is to guess A, because (2) is probably Insufficient. If you are sure that the answer, according to (1), is "No," then there HAVE to be "No" possibilities that work with (2) also, even if you can't find them. Since the Statements can't contradict one another, and you know that "Yes" answers are possible with (2), that's enough to know it's Sufficient.

Obviously this isn't the ideal way to approach a problem, but sometimes this kidn of guessing strategy is better than nothing.