Correct Answer - Option 2 : 8
Concept:
Binomial distribution:
If a random variable X has binomial distribution as B (n, p) with n and p as parameters, then the probability of random variable is given as:
P(X = k) = nCk pk q(n - k) where q = p - 1, n is the number of observations, p is the probability of success & q is the probability of failure.
Note: The mean of a binomial distribution is np and variance is npq.
Calculation:
Given: n = 10, p = 4/5, q = 1/5
As we know that, mean of a binomial distribution = np
\(\rm ⇒Mean = 10 \times \frac{4}{5}=8\)
Hence, the correct option is 2.
