If nCr - 1 = 36, nCr = 84 and nCr + 1 = 126 then ? – McqOptions

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1.	If ⁿC_{r - 1} = 36, ⁿC_r = 84 and ⁿC_{r + 1} = 126 then ?
A.	n = 8, r = 4
B.	n = 9, r = 3
C.	n = 7, r = 5
D.	None of these
Answer» C. n = 7, r = 5

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