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In an A.P., the first term is 2 and the sum of the first five terms is one-fourth of the next five terms. Show that 20th term is -112.

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JBD PUBLICATION-SEQUENCES AND SERIES-EXAMPLE
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  4. Find the sum of all natural numbers lying between 100 and 1000, which ...

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  11. Find the sum of n terms of the following sequences: 8+88+888+……………..up...

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  12. The A.M. between two positive numbers is 34 and their G.M. is 16. find...

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  13. If a be the A.M. and x, y be the two G.M's between b and c, show that ...

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  14. The sum of three numbers which are consecutive terms of an A.P. is 21....

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  18. Find the sum to n terms of the series 3 xx 8 + 6 xx 11 + 9 xx 14 + …

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