GMAT Critical Reasoning (CR) | Re: In the United States, of the young adults who move from one

To weaken the argument, always figure out conclusion in CR.

Here conclusion is - Due to a decrease in the percentage of people attending college, there would be negative economic effect in California.

Premise - Many local businesses are totally driven by college students.

So now pre-phase the possibilities to attack the conclusion:

The percentage in CR - always look for Numbers. The number might not be decreased. If we have a statement saying that Population increases rapidly that without effect
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