GMAT Critical Reasoning (CR) | Re: Since the mayor s publicity campaign for Greenville s bus

Let's first read the question stem - Question is asking us about - most serious doubt on the conclusion - Which means this is a WEAKEN THE ARGUMENT question.

Premise :
1. Mayor's publicity campaign for Greenville's bus service - Lead to decreased automobile traffic into the midtown area by 7%
2. At the same time there has been an equivalent increase in the number of persons riding buses into the middletown

Conclusion :
Mayor's publicity campaign has convinced many people to leave their automobiles
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