drawing conclusions on the gmat will be a shock to your system - especially because of what one might call the hypocrisy involved: the conclusions YOU are supposed to draw are not the same types of conclusions that THEY draw in their passages.

to wit, you are supposed to draw 'autistic style' conclusions - i.e., conclusions that are not even 'conclusions' at all, in the traditional conversational sense of the word. all you're supposed to do is RESTATE, PARAPHRASE, or TRANSFORM the information that's already given in the passage; you are NOT supposed to make ANY assumptions, however reasonable those assumptions may seem.

to eliminate answer choices on drawing conclusions problems, look for ANYTHING that's not explicitly treated in the passage. for instance, if the passage only talks about percentages of GDP, then any choice referring to dollar values of GDP is out of the question. For similar reasons, any answer choice that extrapolates or makes predictions is never going to be the correct answer to one of these problems.

* if you have QUANTITATIVE passages for these problems, MAKE A TABLE OR GRAPH. that will make it much easier to see the relationships between the different quantities in the problems; you'll then be able to see the correct answers, which tend to TRANSFORM the data into different forms, more easily.

* you can get a lot of mileage out of just eliminating all the answer choices that are irrelevant to the passage (where 'irrelevant' includes all the answer choices that contain ANYTHING not directly related to the content of the passage).

* for certain CR problem types (most notably Find an Assumption and Draw a Conclusion), you must STICK TO THE CONTENT OF THE PASSAGE. (in contrast, for other problem types, such as 'strengthen the conclusion', you MUST go OUTSIDE of the passage for additional information.)
-- this simple observation can be a powerful tool for process of elimination. to wit: imagine that a debate judge has handed you a list of the SPECIFICS that are treated in the passage, and will BUZZ you if you mention anything that doesn't show up on that list of specifics. the thing is: correct answers to 'find the assumption' and 'draw a conclusion' problems WON'T GET BUZZED in this situation, because they stick to the specific points actually contained in the passage. you'd be surprised how much mileage you can get from just eliminating the answer choices that get 'buzzed'.

NSNguyen wrote:To draw a conclusion
you must choose the choice that summerize all info about premises in the stem

not true.
in fact, on a great many of these problems, the 'conclusion' comes from a very limited subset of the premises, ignoring large swaths of information from the passage.

in fact, if you try to pick the answer choice that you think "summarizes" the information in the passage, you'll get these problems wrong more often than you'll get them right.
the correct answers to 'draw a conclusion' problems almost never "summarize". usually, they transform or paraphrase chunks of the existing information (though by no means all the existing information).

what you should be looking for is not a summary, but, rather, logical restatements, paraphrases, or immediate consequences of the information contained in the passages.