The sum S of the arithmetic sequence

[silvia_gabriela]

Hi! I'm having some problem understanding the following question on the GMAT Prep Pack 1 - Problem Solving QPS02836:

question deleted by moderator

Thanks,
Silvia

[jlucero]

Hi! I'm having some problem understanding the following question on the GMAT Prep Pack 1 - Problem Solving QPS02836:

question deleted by moderator

Thanks,
Silvia

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