document.write( "Question 1082123: what is the sum of the series 7+22+37...+292? \n" ); document.write( "
Algebra.Com's Answer #696209 by Boreal(15235)\"\" \"About 
You can put this solution on YOUR website!
It is (n/2)(a1+an)
\n" ); document.write( "n-1=285/15, the common difference=19
\n" ); document.write( "n=20
\n" ); document.write( "10*(7+292)=2990
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