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The ratio of sum of the first n terms of...

The ratio of sum of the first n terms of two series in A.P is `(3n + 8) : (7n + 15)`. Prove that the ratio of their 12th terms is 7 : 16.

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KALYANI PUBLICATION-PROGRESSION-EXERCISE
  1. If {S1,S2,S3} denoted the sum of n terms of three series in A.P. the f...

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

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  3. The ratio of sum of the first n terms of two series in A.P is (3n + 8)...

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  4. In an A.P. the pth and qth terms are respectively a and b. Show that t...

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  5. If the first terms, second term and the last term of an A.P. are respe...

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  6. The sum of first n terms of an A.P. is Sn.If Sn=n^2p and Sm=m^2p(mn...

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  7. The first term of an A.P. is a. If sum of first p terms is zero, pro...

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  8. The sum of first P terms of an A.P. is equal to that of the first Q te...

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  9. Find the sum of all odd numbers lying between 12 and 90.

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  10. Determine the sum of the numbers lying between 100 and 500 which are d...

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  11. Find the sum of all numbers lying between 1 and 100 which are divisibl...

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  12. Determine the sum of the numbers lying between 100 and 200 which are n...

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  13. Determine the sum of following series upto n terms. 1.2+2.3+3.4+…….

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  14. Determine the sum of following series upto n terms. 1.1+2.3+3.5+…….

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  15. Determine the sum of following series upto n terms. 2.1+3.3+4.5+…….

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  16. Determine the sum of following series upto n terms. 3.8+6.11+9.14+……...

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  17. Determine the sum of following series upto n terms. 1.3+2.4+3.5+…….

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  18. Determine the sum of following series upto n terms. 1.3+5.7+9.11+…….

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  19. Determine the sum of following series upto n terms. (3^2-2^2)+(5^2-4...

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  20. Determine the sum of following series upto n terms. (1^2-2^2)+(3^2-4...

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