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In an A.P., 1^(st) terms is 1 and the la...

In an A.P., `1^(st)` terms is 1 and the last term is 20. The sum of all terms is 399 then n = ………….

A

`42`

B

`38`

C

`21`

D

`19`

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UNIQUE PUBLICATION-ARITHMETIC PROGRESSION-Problem Set 3
  1. For an A.P. if t(7)=4.d=-4.then a=…..

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  2. For an A.P. if a=3.5,d=0,n=101, then t(n)=….

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  3. In an A.P. first two terms are -3,4 then 21^(st) term is………

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  4. If for an A.P.,d=5, then t(18)-t(13)=….

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  5. Sum of first five multiples of 3 is……….

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  6. 15,10,5…..In this A.P. sum of first 10 terms is….

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  7. In an A.P., 1^(st) terms is 1 and the last term is 20. The sum of all ...

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  8. The 4th term from the end of an AP -11, -8, -5, …, 49 is

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  9. In an A.P. 10^(th) term is 46, sum of 5^(th) and 7^(th) term is 52. fi...

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  10. The A.P. in which 4^(th)term -15 and 9^(th) term is -30. Find the sum ...

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  11. Two A.P's are given 9,7,5..and 24,21,18,….If n^(th)term of both the pr...

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  12. If sum of 3^(rd) and 8^(th) terms of an A.P. is 7 and sum of 7^(th) an...

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  13. In an A.P., first term is -5 and last term is 45. If sum of all the nu...

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  14. Sum of 1 to n natural numbers is 36, then find the value of n.

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  15. Split 207 into three parts such that these are in A.P. and the product...

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  16. An AP consists of 37 terms. The sum of the three middle most terms is ...

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  17. Show that the sum of an A.P. whose first term is a, the second term is...

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  18. The sum of first P terms of an A.P. is equal to the sum of its first Q...

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  19. If m times the m^(t h) term of an A.P. is equal to n times its n^(t h)...

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  20. Rs. 1000 is deposited at 10 per cent simple interest. Check if the int...

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