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The sum of fIrst n terms of an A.P serie...

The sum of fIrst n terms of an A.P series is `26n-2n^2`. Find the fifth term.

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If the sum of the first n terms of an AP is 4n-n^2 ,what is the first term(that is S_1 )?What is the sum of first two terms?What is the second term?Similarly,find the 3rd,the 10th and nth terms.

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If the sum of first nine terms of an A.P is 171 and that of first 24 terms is 996,find the sum of first 41 terms.

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KALYANI PUBLICATION-PROGRESSION-EXERCISE
  1. Show that the sum of 500 A.M.’s between 2 and 3 is 1250.

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  2. Prove that the ratio of the sum of m A.M.’s between any two n...

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  3. The sum of fIrst n terms of an A.P series is 26n-2n^2. Find the fifth ...

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  4. Find the rth term of an A.P., the sum of whose first n terms is 2n+3n^...

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  5. The first term and common difference of an A.P. are 3 and 2 respective...

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  6. The fifth and ninth terms of an A.P. are respectively -15 an...

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  7. The first term and common difference of an A.P. are respectively 4 and...

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  8. The first term and common difference of an A.P. are respectively -2 an...

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  9. The first term and last term of an A.P. are respectively 1 and 157. If...

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  10. The first term and last term of an A.P. are 5 and 123 respectively. ...

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  11. If the sum upto 21st term of an A.P. is 630, determine the 11th ...

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  12. If 18th term of an A.P. is 52, determine the sum upto 35th term.

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  13. In an A.P. if the ratio of the sum upto 10th term and the 10th...

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  14. The seventh term of an A.P. is 20 and the sum of first twenty terms ...

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  15. The sum of first ten terms of an A.P. is 120. The sum of next ten term...

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  16. In an A.P. the ratio of 7th term to 11th term is 19 : 31 and the sum ...

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  17. The sum of first nine terms of an A.P. is 171 and that of 24 terms is ...

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  18. In an A.P. the nth term is p and the sum of first n terms is q. Show t...

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  19. If {S1,S2,S3} denoted the sum of n terms of three series in A.P. the f...

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  20. The sum of first n terms of an A.P. is m and that of first m terms is...

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