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If 15C(3r) = 15C(r+3) than r = '...

If `15C_(3r) = 15C_(r+3)` than `r = '

A

a.5

B

b.4

C

c.3

D

d.2

Text Solution

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The correct Answer is:
C
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HIMALAYA PUBLICATION-PERMUTATION AND COMBINATIONS-Question Bank
  1. If 15C(3r) = 15C(r+3) than r = '

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  2. If 20C(r) = 20C(r-10) than 18C(r)=

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  3. Which of the following is not correct?

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  6. nCr+2. nC(r-1)+nC(r-2)=

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