document.write( "Question 855044: What is Sn of the geometric series with a1=-81, r=-2/3, and n=5?\r
\n" ); document.write( "\n" ); document.write( "A)26
\n" ); document.write( "B) -39
\n" ); document.write( "C) -55
\n" ); document.write( "D)211
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Algebra.Com's Answer #515046 by richwmiller(17219)\"\" \"About 
You can put this solution on YOUR website!
S=a*(1 - r^n)/(1 - r)
\n" ); document.write( "S=-81*(1 - (-2/3)^5)/(1 - (-2/3))
\n" ); document.write( "S = -55
\n" ); document.write( "C) -55
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