shadowsjc wrote:Hi,
I unfortunately sold my copy of the CR Bible already, so I can''t reference any specific pages. However, I think you're dwelling too much on the whole concept of Sufficient vs Necessary.
If A -> then B
A is sufficient, B is necessary.
On the GMAT, they won't ask you specific questions about which is which. It's useful to be able to differentiate which is which in some questions.
I don't remember ever encountering a question where the answer is just a restatement of one of the premises. Can you post a full question and answer choices of an example so I can see what you're talking about? Usually the questions that say "the conclusion can not be true unless which of the following is true" have answers that are not stated in the passage.
For Example:
The Highway Safety Institute reports that the PZ 1000 has the fewest injuries per accident of any car in its class. This shows that the PZ 1000 is one of the safest vars available today.
The stem asks which answer weakens the argument. My frist Cause and Effect notes were this: Cause: PZ 1000 has less injuries than cars in its class. Effect: PZ 1000 is one of the safest cars.
So using the CR BIBle techniques I tried to show that there is another reason the car is safe or that maybe the relationship is reversed or other cars(not in its class were safer). However, the answer compares the PZ 1000 to cars in its class, which is in the premise. This is the answer:
CArs in in the class to which the PZ 1000 belongs are more likely to be involved in accidents than are other types of cars.
Another example is question 22 in GMAT verbal.
Hope I make sense, or maybe I am digging too much. Thanks for your help and Congrats on your amazing GMAT score.
