document.write( "Question 843062: find the sum when N=20 ,A=2 and D=5 for S=N/2(2a+(N-1)d \n" ); document.write( "
Algebra.Com's Answer #507859 by ewatrrr(24785)\"\" \"About 
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document.write( "Hi,
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document.write( "N=20 ,A=2 and D=5
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document.write( "\"+S=%28N%2F2%29%282a%2B%28N-1%29d%29\"
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document.write( " S=20/2(2•2 +(19)5)= 3800
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document.write( " S=10(99)= 990 \n" );
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