Answer:
0.0537
Explanation:
This follows a binomial distribution with : n
Number of trials 'N' = 12 ; Probability of success (difference between speakers) 'p' = 1/2 or 0.5 ; Probability of failure (no difference b/w speakers) = 1/2 or 0.5 ; No of success 'r' = 3
P (X = 3) =
= 12C3 (0.5)^3 (0.5)^9
0.0537