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IF ""^(n) C((r-1))=36 ,""^(n)C(r)=84 ,...

IF ` ""^(n) C_((r-1))=36 ,""^(n)C_(r)=84 , ""^(n)C_(r+1)=126 `, then r=

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1

B

3

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5

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7

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DIPTI PUBLICATION ( AP EAMET)-PERMUTATIONS & COMBINATIONS-EXERCISE 1B (COMBINATIONS )
  1. IF ""^(n) C(r-1) : ""^(n )C(r) : = 2: 4 : then (n,r)=

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  2. IF ""^((n+1))C((r+1)): ""^(n)C(r) : ""^((n-1))C((r-1))=11:6:3 then (...

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  3. IF ""^(n) C((r-1))=36 ,""^(n)C(r)=84 , ""^(n)C(r+1)=126 , then r=

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  4. ""^(n) C(r-1) = 330 ,""^(n)C(r)=462 , ""^(n)C(r+1) = 462 implies r=

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  5. "Prove that "(""^(4n)C(2n))/(""^(2n)C(n))=(1.3,5......(4n-1))/({1.3.5....

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  6. (2^(n) [1.3.5. . .(2n-1) ])/(n!)=

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  7. If S(n) = underset (r=0) overset( n) sum (1) /(""^(n) C(r)) and T...

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  8. The ratio of ""^(24 ) C(r) to ""^(25 ) C(r) when each of them h...

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  9. The difference between the greatest values of ""^(15)C(r) and ""...

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  10. The number of ways in which 6players can be selected from a b...

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  11. The number of ways in which 5players are selected from 10 players so ...

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  12. The number of ways that 6 questions can choose out of 9 question ...

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  13. The number of ways that a cricket eleven can be chosen out of ...

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  14. The number of ways in which a term of eleven players can be sele...

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  15. The number of ways in which 7 players can be selected from a b...

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  16. A father takes 8 children 3 at a time to the zoo , as often a...

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  17. A person wishes to make up as many different parties of 10 as ...

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  18. A guard of 12 men is formed a group of n soldiers . It is found...

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  19. From a company 15 soldiers any 4 are from 8 male & 7 female a...

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  20. The number of ways of selecting 6 clerks from 8 male &7 female ap...

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