document.write( "Question 51319: The number of terms in a Arithmetic progression is even,the sum of the odd terms is 24 and sum of the even terms is 30 and if the last term exceeds the first term by 21/2,find the numbers \n" ); document.write( "

Algebra.Com's Answer #34264 by venugopalramana(3286) $\"\"$ $\"About$

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The number of terms in a Arithmetic progression is even,the sum of the odd terms is 24 and sum of the even terms is 30 and if the last term exceeds the first term by 21/2,find the numbers
\n" ); document.write( "LET FIRST TERM =A
\n" ); document.write( "LAST TERM = A+21/2=A+10.5
\n" ); document.write( "LET NUMBER OF TERMS =2N
\n" ); document.write( "A+10.5=A+(2N-1)D
\n" ); document.write( "D=10.5/(2N-1)...2D=21/(2N-1)
\n" ); document.write( "SUM OF ODD TERMS = A+(A+2D)+(A+4D)+..............N TERMS
\n" ); document.write( "=(N/2)[2A+(N-1)2D]=(N/2)[2A+(N-1)*21/(2N-1)]=24...........1
\n" ); document.write( "SUM OF EVEN TERMS = (A+D)+(A+3D)+......N TERMS
\n" ); document.write( "=(N/2)[2A+21/(2N-1) + (N-1)21/(2N-1)]=30.............2
\n" ); document.write( "EQN.2-EQN.1
\n" ); document.write( "(N/2)[21/(2N-1)]=6
\n" ); document.write( "21N=12(2N-1)=24N-12
\n" ); document.write( "3N=12
\n" ); document.write( "N=4
\n" ); document.write( "D=10.5/(2*4-1)=1.5
\n" ); document.write( "A=1.5 \n" ); document.write( "

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