GMAT Data Sufficiency (DS) | Re: In a school election, Joan and Peter were the only candidates for

Joan - 390 Senior votes
Peter - 336 Junior votes

Statement 1: Joan received 40% of the votes cast by seniors

This means the 390 of the votes cast by seniors received by Joan represents 40% of the votes cast by seniors. So the rest of the 60% of the votes cast by seniors was received by Peter.

So

Number of Votes cast by Seniors received by Peter = 60 * 390/40 = 585

So by this statement we know

Joan - 390 Senior votes , don't know??
Peter - 585 Senior votes , 336 Junior votes

Since, this
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