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In an A.P, 1st term is 1 and the last te...

In an A.P, `1st` term 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`

A

42

B

38

C

21

D

19

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CHETANA PUBLICATION-Arithmetic Progression-EXERCISE
  1. Sum of first five multiples of 3 is……a)45 b)15 c)55 d)35

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  2. 15, 10, 5,…… In this A.P the sum of first 10 terms is…..a)-75 b)-125 c...

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  3. In an A.P, 1st term is 1 and the last term is 20.The sum of all terms ...

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  4. For the A.P: 4,9,14…… t11=…..a)49 b)54 c)59 d)44

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  5. If a=6, d=3, then S10=……a)192 b)195 c)198 d)201

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  6. The sum of first 10 natural numbers is ..... a)55 b)155 c)310 d)210

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  7. Which of the following sequence is not an A.P? a)0.5,2,3.5,5,…. b)3,5,...

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  8. Find the missing term in the A.P: -5, ...., 13 a)1 b)4 c)2 d)3

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  9. Find the t2 of the sequence for which S1=2,S2=12 and S3=30 a)24 b)1 c)...

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  10. For an A.P if t4=12 and d=-10, then find a. a)-18 b)42 c)-5 d)21

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  11. The next two terms of the given sequence 1,3,7,15,31….. are: a)42, 54 ...

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  12. In an A.P, a=8, tn=62, Sn=210, then find n. a)5 b)6 c)7 d)8

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  13. The sum of first n terms of an A.P. is Sn=………… a)n/2[t1+tn] b)n/2[2+(n...

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  14. A meeting hall has 30 rows in all. There are 20 seats in the first row...

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  15. State whether the given sequence is an A.P or not : 1^3,2^3,3^3,4^3,5^...

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  16. Is the following sequence Arithmetic Progression? If it is an A.P then...

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  17. Is the following sequence an Arithmetic progression? If it is an A.P t...

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  18. Is following sequence an Arithmetic progression? If it is an A.P then ...

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  19. Is the following sequence an Arithmetic progression? If it is an A.P t...

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  20. Is the following sequence is an Arithmetic progression? If it is an A....

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