\[^{n}{{C}_{r}}{{\div }^{n}}{{C}_{r-1}}=\] [MP PET 1984] – McqOptions

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1.	\[^{n}{{C}_{r}}{{\div }^{n}}{{C}_{r-1}}=\] [MP PET 1984]
A.	\[\frac{n-r}{r}\]
B.	\[\frac{n+r-1}{r}\]
C.	\[\frac{n-r+1}{r}\]
D.	\[\frac{n-r-1}{r}\]
Answer» D. \[\frac{n-r-1}{r}\]

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