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If the first term of an A.P. is 2 and th...

If the first term of an A.P. is 2 and the sum of first five terms is equal to one-fourth of the sum of the next five terms, show that the 20th term is -112.

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ICSE-SEQUENCE AND SERIES -CHAPTER TEST
  1. How many terms of the A.P., -6,(-11)/(2),-5 ... are needed to give the...

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  2. Determine the sum of the first 35 terms of an A.P. if a(2), = 2 and a(...

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  3. If the first term of an A.P. is 2 and the sum of first five terms is e...

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  4. Insert 3 arithmetic means between 2 and 10.

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  5. Find 12th term of a G.P. whose 8th term is 192 and the common ratio is...

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  6. The first term of a G.P. is 1. The sum of the third and fifth terms is...

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  7. The sum of first three terms of a G.P. is (39)/(10) and their product ...

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  8. The sum of some terms of a G.P. is 315 whose first term and the common...

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  9. Find the sum of the series 0.6 +0.66 +0.666+ ... to the n terms

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  10. The sum of an infinite series is 15 and the sum of the squares of thes...

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  11. Insert three geometric means between 1 and 256.

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  12. In the sum to infinity of the series 3+(3+x) (1)/(4) + (3+2x)(1)/(4^(2...

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  13. Find the sum to n terms of the series 3.8 +6.11 +9.14 + ...

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  14. Find the sum 5^(2)+ 6^(2) + 7^(2) + ... + 20^(2).

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  15. If in a geometric progression consisting of positive terms, each term ...

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  16. If the first term of an infinite G.P. is 1 and each term is twice the ...

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  17. If fifth term of a G.P. is 2, then the product of its first 9 terms is

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  18. The sum of three decreasing numbers in A.P. is 27. If-1,-1, 3 are adde...

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  19. The first two terms of a geometric progression add up to 12. The sum o...

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  20. The sum to infinity of the series 1+2/3+6/3^2+14/3^4+...is

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