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The number of combinations of n differen...

The number of combinations of n different of n different things taken r at a time in which p particular things never occur is -

A

`.^(n-p)C_(r-p)`

B

`.^(n-p)C_(r)`

C

`.^(n)C_(r)`

D

`((n-p)!)/(r!)`

Text Solution

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The correct Answer is:
B
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