The correct option (b) 1 - [{(2n)!}/{(n!)2}] ∙ (1/4n)
Explanation:
coin is tossed 2n times
Required probability = 1 – [probability that number of Head equal to number of tail = n]
= 1 – [(2nCn)(1/2)n(1/2)n]
= 1 – [{(2n!)/[(n!)(n!)]} (1/4n)]
= 1 – [{(2n)!}/{(n!)2}] ∙ (1/4n).