document.write( "Question 471082: what is the possible answer to the \"?\" in the series?
\n" ); document.write( "the question is 50, 70, ? ,90, ?, ?\r
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Algebra.Com's Answer #323377 by richard1234(7193)\"\" \"About 
You can put this solution on YOUR website!
That is a sequence, not a series (series is the sum of the terms in a sequence). Also, if the question marks represent the same number, then there is no definite sequence. There could possibly be a sequence {50, 70, 80, 90, 95, 97.5} which is similar to a geometric sequence. \n" ); document.write( "
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