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""^(n) p (r) = 3024 and ""^(n) C (r) = 1...

`""^(n) p _(r) = 3024 and ""^(n) C _(r) = 126,` then r is : a)5 b)4 c)3 d)2

A

5

B

4

C

3

D

2

Text Solution

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The correct Answer is:
B
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