document.write( "Question 259658: three numbers are in AP and their sum is 21. if 1,5,15 are added to them respectively,they form a GP.The numbers are.
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document.write( "please tell me the solution and method of solving this type of questions using this formula for Ap:(a-d),a, (a+d) and for GP:a/r,a,ar
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document.write( "the option for the above question is :A)5,7,9 B)9,7,5 C) none of these\r
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document.write( "the above is question of AP and GP.
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Algebra.Com's Answer #191104 by Fombitz(32388)![]() ![]() You can put this solution on YOUR website! Let A be your starting number, d be the difference for the arithmetic progression. \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "Then from the geometric progression information, \n" ); document.write( "First: \n" ); document.write( "Second: \n" ); document.write( "Third: \n" ); document.write( "Since they are in geometric progression, each successive pair equals the common ratio. \n" ); document.write( " \n" ); document.write( "From eq. 1, you know, \n" ); document.write( " \n" ); document.write( "Substitute, \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "Again using eq. 1, \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "You can factor, \n" ); document.write( " \n" ); document.write( "Two solutions: \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( ". \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( ". \n" ); document.write( ". \n" ); document.write( "A) (5,7,9) is one solution. \n" ); document.write( "But (23, 7, -9) is also a solution. \n" ); document.write( " |