If X follows a binomial distribution with n = 20 and probability of success p = 0.3, what is its expected value?
Correct answer: B. 6
- A. 3
- B. 6
- C. 7
- D. 20
Explanation
The mean of a binomial distribution is np. Therefore, E(X) = 20 × 0.3 = 6, while 20 is the number of trials rather than the expected number of successes.
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