document.write( "Question 1177527: The sum of the first 10 terms of an arithmetic progression is 80 and the sum of the next 12 terms is 624. What is the arithmetic progression?\r
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Algebra.Com's Answer #806582 by jitendra_maths(6)\"\" \"About 
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Let first term = a and common difference = d
\n" ); document.write( "S_10=10/2 [2a+(10-1)d]=80
\n" ); document.write( " (2a+9d)=16 ---------------- (i)\r
\n" ); document.write( "\n" ); document.write( "Also sum of next 12 terms is 624
\n" ); document.write( "Hence sum of first 22 terms = 624+80 = 704
\n" ); document.write( "Therefore, S_22= 22/2 [2a+(22-1)d]=704
\n" ); document.write( " 2a + 21d = 64 ------------------------(ii)
\n" ); document.write( " On solving (i) and (ii)
\n" ); document.write( "(2a + 21d) - (2a+9d) = 704 - 16
\n" ); document.write( "12d = 48
\n" ); document.write( "d = 4
\n" ); document.write( "from equation (i) 2a + 36 = 16
\n" ); document.write( "a= -10\r
\n" ); document.write( "\n" ); document.write( "Hence required AP is
\n" ); document.write( "-10, -6, -2, 2, 6, 10, 12, …………..
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