If nCr+1 = nC8 then find the value of 22Cn.
Given: nCr+1 = nC8 Need to find: Value of 22Cn We know, one of the property of combination is: If nCr = nCt, then, (i) r = t OR (ii) r + t = n We are going to use property (i) nCr+1 = nC8 By the property (i), ⇒ r + 1 = 8 ⇒ r = 7 Now we are going to use property (ii) ⇒ n = 8 + 7 + 1 = 16 Therefore, 22Cn = 22C16 = 74613.